byd F3 (2015) Workshop manual

BYD AUTO BYD NEW F3 Maintenance & Repair Manual

I

Engine Management System

Contents

Chapter 1 473Q M7.9 Management System Service Manual ....................................................... 1

Part 1 EFI System Service Notice ......................................................................................... 3

Part 2 Introduction to M7 System .......................................................................................... 6

Part 3 M7 System Component Structure, Principle and Troubleshooting ............................. 12

Part 4 Diagnostic Procedures of Servicing M7 System as per DTC ..................................... 50

Part 5 Diagnostic Procedures of Servicing M7 System as per Symptoms of Malfunction ..... 70

Part 6 Guide for Use of BYD-ED300 Electric Diagnostic Tester .......................................... 82

Part 7 Accessories .............................................................................................................. 85

Chapter 2 473QE Engine Electronic Control System ..................................................................... 96

Part 1 EFI System Service Notice ....................................................................................... 99

Part 2 Introduction to MT22.1 System ............................................................................... 101

Part 3 MT22.1 System Component Structure, Principle and Troubleshooting .....................113

Part 4 Diagnostic Procedures of Servicing MT22.1 System as per DTC ............................ 147

Part 5 Diagnostic Procedures of Servicing MT22.1 System as per Symptoms of Malfunction

......................................................................................................................................... 190

Part 6 Guide for Use of BYD-ED400 Electric Diagnostic Tester ........................................ 201

Part 7 Accessories ............................................................................................................ 212

Chapter 3 483QA M7 Management System ............................................................................... 218

Part 1 EFI System Service Notice ..................................................................................... 220

Part 2 Introduction to M7 System ...................................................................................... 224

Part 3 M7 System Component Structure, Principle and Troubleshooting ........................... 234

Part 4 Diagnostic Procedures of Servicing M7 System as per Symptoms of Malfunction ... 293

Part 5 Guide for Use of M7 System Diagnostic Tester ....................................................... 307

Part 6 Accessories ............................................................................................................ 308

1

Chapter 1 473Q M7.9 Management System Service Manual

Contents

Part 1 EFI System Service Notice ................................................................................................ 3

Section 1 General Service Notice ........................................................................................ 3

Section 2 Notice During Service .......................................................................................... 3

Section 3 List of Service Tools ............................................................................................. 4

Section 4 Note for Abbreviations in the Manual ................................................................... 6

Part 2 Introduction to M7 System ................................................................................................. 6

Section 1 Basic Principles ................................................................................................... 6

Section 2 Control Signal: M7 System I/O Signal .................................................................. 8

Section 3 System Functions ................................................................................................ 9

Section 4 Introduction to System Malfunction Diagnosis .................................................... 10

Section 5 Description of Related Problems ........................................................................11

Part 3 M7 System Component Structure, Principle and Troubleshooting .................................... 12

Section 1 Introduction to Engine Management System Component Layout ....................... 12

Section 2 Intake Air Pressure and Temperature Sensor ..................................................... 14

Section 3 Throttle Position Sensor .................................................................................... 17

Section 4 Coolant Temperature Sensor ............................................................................. 19

Section 5 Knock Sensor .................................................................................................... 21

Section 6 Oxygen Sensor.................................................................................................. 24

Section 7 Crankshaft Position Sensor ............................................................................... 28

Section 8 Camshaft Position Sensor ................................................................................. 31

Section 9 Electronic Controller Unit ................................................................................... 33

Section 10 Electric Fuel Pump .......................................................................................... 36

Section 11 Fuel Injector ..................................................................................................... 39

Section 12 Idle Speed Stepper Motor ................................................................................ 42

Section 13 Ignition Coil ..................................................................................................... 45

Section 14 Carbon Canister Control Valve ........................................................................ 47

Section 15 Fuel Distribution Pipe Assembly ...................................................................... 49

Part 4 Diagnostic Procedures of Servicing M7 System as per DTC ............................................ 50

Part 5 Diagnostic Procedures of Servicing M7 System as per Symptoms of Malfunction ............ 70

Section 1 Engine Running Slowly or Not Running When Started ....................................... 70

Section 2 Engine Cannot Be Started with Starter Running ................................ ................. 71

Section 3 Hard to Start When the Engine Is Hot ................................................................ 72

Section 4 Hard to Start When Engine Is Cold .................................................................... 73

Section 5 Hard to Start at Normal Engine Speed Any Time ................................................ 74

Section 6 Engine Normally Started, yet Idling Unstable Any Time ...................................... 75

Section 7 Engine Normally Started, Idling Unstable During Heating ................................... 76

Section 8 Engine Normally Started, yet Idling Unstable after Heating ................................ 77

Section 9 Engine Normally Started, yet Idling Unstable or Stalling Under Partial Load (e.g.

A/C Turned on) ................................................................................................................. 78

Section 10 Engine Normally Started, yet Idling at a Higher Speed ................................ ..... 78

Section 11 Engine Running Slowly or Stalling During Acceleration .................................... 79

Section 12 Slow Response in Acceleration ........................................................................ 80

Section 13 Sluggish Acceleration and Poor Performance .................................................. 81

Part 6 Guide for Use of BYD-ED300 Electric Diagnostic Tester ................................................. 82

Section 1 Preparation for Troubleshooting with BYD-ED300 ............................................. 83

Section 2 Instructions for Keypad Operation...................................................................... 83

Section 3 Functions .......................................................................................................... 85

Part 7 Accessories ..................................................................................................................... 85

Section 1 Table of Mounting Torque for Parts .................................................................... 93

Section 2 Rules for Maintenance of EFI System ................................................................ 93

2

Foreword

With the development of China's national economy, car ownership is increasing, and environmental regulations are stricter. Since the combination of closed-loop control gasoline rationing technology and three-way catalytic converter would reduce the toxic substance emissions of vehicles by more than 92%, it had become an irreversible trend to replace carburetors with EFI technology. This indicated that the era of carburetor engine in China's auto industry had ended, and the era of EFI engine had begun.

The engine management system provided for BYD 473Q engine is the MOTRONIC system provided by United Automotive Electronic Systems Co., Ltd. As the largest and most influential supplier of automotive engine EFI systems in China, United Automotive Electronic Systems Co., Ltd. started to supply MOTRONIC series EFI systems and parts imported from BOSCH for major domestic car companies from 1996. The so-called MOTRONIC is a trade name, which does not have a specific meaning. The MOTRONIC system has certain technical characteristics, that is, the electronic fuel rationing control and the ignition timing electronic control system of the engine are combined to share a set of sensor, electronic control unit and power supply device. It goes without saying that MOTRONIC system features ignition timing control function, which has significantly improved the engine performance.

Same as other EFI systems, MOTRONIC system can greatly reduce car emissions on the one hand; on the other hand, it will bring difficulties to service personnel familiar with the traditional carburetor engines only. Carburetor engines are visible and palpable to service personnel. However, the EFI engines do not have the mechanical components that people previously familiar with, and are replaced by a variety of electronic components. Originally, service personnel and even the drivers may adjust the carburetor or distributor; however, the data are stored in the computer chip now, so that the general service staff can not eliminate malfunctions by modifying the data with electronic instrument. It is often invisible when the electronic components of the system have failures, so that it requires a variety of instruments to test and identify. The service personnel often feel difficult to repair the EFI engines. According to this reality, we write this Service Manual, and hope to play a role in two aspects: to help the engineers of engine plants or vehicle factories better understand the electronic engine control systems; on the other hand, to help the service personnel repair EFI engines.

This Manual first describes the composition and working principle of EFI systems. Then, the structure and performance of the various system components are described in details. Generally, electric diagnostic tester is an essential tool in the service process of EFI systems. Electric diagnostic tester can call out the malfunction information stored in the ECU. To help readers understand the true meaning of each DTC, the Manual lists the conditions that ECU sets various malfunction information records. However, many malfunctions can’t be directly identified basing on the malfunction information records; instead, a series of analysis is required to locate the malfunction. Therefore, the Manual detailedly describes how to locate the malfunction according to the malfunction information records.

Due to the presence of the electronic control components, the reasons of engine malfunction have new contents. In other words, an engine malfunction may be caused by either mechanical reasons or electronic components. Moreover, the actual engine malfunctions are not identified with electric diagnostic tester only. Therefore, the Manual also identifies the malfunctions with electronic control system according to the engine symptoms.

3

Part 1 EFI System Service Notice

Section 1 General Service Notice

1.1 You are only allowed to check the EFI

system with a digital multimeter.

1.2 Please use the quality parts for service;

otherwise, the EFI system may not work normally.

1.3 Only unleaded gasoline can be used

during service.

1.4 Please comply with the service

procedures.

1.5 No one is allowed to disassemble the

parts of EFI system during service.

1.6 Handle the electronic elements (ECU,

sensor, etc.) very carefully during service, to avoid dropping to the ground.

1.7 Build up an environmental awareness and

treat the wastes produced during service effectively.

Section 2 Notice During Service

2.1 To ensure normal working of the EFI

system, do not remove any parts or its connectors from its mounting position so as to avoid unexpected damage and prevent foreign matters such as moisture and greasy dirt from entering the connector.

2.2 Be sure to turn off the ignition switch

before you connect or disconnect the connectors; otherwise, damage may be caused to the electric elements.

2.3 Keep the ECU temperature lower than

80°C in simulating the hot condition of malfunction or other service operations which may cause a temperature rise.

2.4 The EFI system has a much higher fuel

supply pressure (about 350kPa), so high-pressure resistant fuel pipes are used for all the fuel pipelines. Even if the engine is not running, the fuel pressure is much higher in the oil line. Therefore, do not easily disassemble the fuel pipes during maintenance; if the fuel system requires maintenance, please release the pressure of the fuel system in the following method before removing the fuel

pipes: start the engine and let it idle, connect the diagnostic apparatus, enter

―Actuator Test‖ and shut off the fuel pump,

until the engine flames out automatically.

Only professional service technicians are allowed to disassemble the pipeline and replace the fuel filter at a well-ventilated place.

2.5 Do not power on the electric fuel pump when you remove it from the fuel tank, as it may cause electric spark or even fire.

2.6 You are not allowed to conduct a running

test to the fuel pump when it is dry or in water; otherwise, its service life may be shortened. In addition, its positive and negative poles shall be properly connected.

2.7 To check the ignition system, spark-over

test can be taken only when necessary. Such a test shall be completed in a short time and the throttle valve cannot be opened during test; otherwise, it may cause a lot of unburned gasoline entering the bleeding pipe and damage the three-way catalytic converter.

2.8 The idle speed adjustment can be

completed by the EFI system, which requires no manual operation. Users are not allowed to adjust the throttle limit screws which have been properly adjusted by the manufacturer.

2.9 The positive and negative terminals of battery shall be properly connected so as to avoid any damage to electronic components. Negative grounding is adopted for this system.

2.10 Do not remove the battery cable when

the engine is running.

2.11 Remove the positive and negative cable

of battery as well as the ECU before electric welding on the car.

2.12 Do not check the electric input/output

signals of parts by piercing the cable sheath.

4

Section 3 List of Service Tools

Tool name:

Electric Diagnostic Tester

Function: Read/clear the DTC of EFI system, observe data streams, conduct component action tests, etc.

Tool name:

Digital Multimeter

Function: Check the characteristic parameters of EFI system, such as voltage, current and resistance.

Tool name:

EFI System Adapter

Function: Check the electric signals of each ECU pin, check the line, etc.

Tool name:

Ignition Timing Light

Function: Check the engine ignition timing, etc.

Tool name:

Vacuum Meter

Function: Check the pressure in the intake manifold.

Tool name:

Cylinder Pressure Gauge

Function:

5

Check the pressure of each cylinder.

Tool name:

Fuel Pressure Gauge

Function: Check the pressure of fuel system, and judge the working condition of fuel pump and fuel pressure regulator in the fuel system.

Tool name:

Fuel Injector Cleaning Analyzer

Function: Analyze the cleaning of fuel injector.

Tool name:

Exhaust Gas Analyzer

Function: Check the exhaust emission of the vehicle and help to judge the EFI system malfunction.

6

DG

Crankshaft Position Sensor (Engine Speed Sensor)

DKG

Throttle Position Sensor

DLA

Idle Speed Stepper Motor

DS-S-TF

Intake Pressure and Temperature Sensor

ECU

Electronic Control Unit (commonly known as: computer)

EKP

Fuel Pump

EMS

Engine Management System

EV

Fuel Injector

LSH

Heated Oxygen Sensor

KS

Knock Sensor

KSZ

Fuel Distributing Pipe Assembly

KVS

Fuel Distributing Pipe

PG

Camshaft Position Sensor (also known as Phase Sensor)

TEV

Carbon Canister Control Valve

TF-W

Coolant Temperature Sensor

ZSK

Ignition Coil

Sensor

ECU

Actuator

Engine

Diagnosis

Section 4 Note for Abbreviations in the Manual

Part 2 Introduction to M7 System

Section 1 Basic Principles

1.1 System Overview: M7-Motronic EMS (Engine Management System) EMS mainly consists of the sensor, microprocessor (ECU), and actuator, which will control the air intake amount, fuel injection quantity and ignition advance angle when the engine is running. The basic structure is shown in Fig. 2-1.

Fig. 2-1 Components of Engine Electronic Control System

In the engine electronic control system, the sensor is used as the input part to measure various physical signals (temperature, pressure, etc.), and convert into corresponding electrical signals; ECU is used to receive input signals from the sensor, calculate and process according to set procedure, generate corresponding control signal and output to the power drive circuit, which will run the engine in accordance with the established control strategy by driving the respective actuators to perform different actions; meanwhile, the fault diagnostic system for the ECU monitors every component or control function in the system; once the fault is detected and confirmed, the fault code is stored, and the "limp home" function is called; when the fault has been eliminated, the normal value is restored.

The biggest advantage of M7 EMS is the torque-based control strategy, which aims to link a large variety of control targets together and is the only way to integrate each function into the different

7

Electronic Control Unit (ECU)

Idle Speed Stepper Motor

Intake Pressure and Temperature Sensor

Fuel Injector

Coolant Temperature Sensor

Electric Fuel Pump

Throttle Position Sensor

Fuel Pressure Regulator

Crankshaft Position Sensor

Pump Holder

Crankshaft Position Sensor

Fuel Distributing Pipe

Knock Sensor

Carbon Canister Control Valve

Oxygen Sensor

Ignition Coil

ECU variants as per the engine and vehicle model. M7 engine electronic control system mainly consists of:

M7-Motronic EMS is an electronically-operated gasoline engine control system, which provides many control characteristics related to operator and vehicle or equipment. This system combines the open-loop and closed-loop (feedback) control modes to provide various control signals for running the engine. Basic management functions physical model applied engine

 Torque-based system structure  The cylinder load is determined by the intake air pressure sensor / air flow sensor  Improved air-mix control function in both static and dynamic state   Closed-loop Control  Fuel injection in cylinder order  Ignition timing, including knock control in cylinder order  Emission control function  Catalytic converter heating  Carbon canister control  Idle speed control  Limp home

1.2 Torque Structure: Torque Controlled M7 System In the torque-controlled M7 system, all the internal and external demands for the engine are defined as the torque or efficiency requirements of the engine, as shown in Fig. 2-2. The requirements of engine are converted to torque or efficiency control variables, which then will be processed in the central torque demand coordinator module. M7 system can sort these conflicting requirements by priority, carry out the most important one and obtain such parameters as the required fuel injection time and ignition timing by the torque converting module. Executing this control variable will not affect other variables. This is the advantage of torque-controlled system.

During engine matching, due to the variable independence of torque-controlled system, only the engine data are used to match the engine characteristic curve and pulse spectrum, and won’t interfere with other functions and variables, which will avoid repeated calibration, simplify the matching process and reduce the cost of matching.

8

Efficien

Efficiency requirements

Engine startup Catalytic heating Idle speed contro

External torque requests

Cruise control Vehicle speed limit Vehicle dynamic control Drivability

Internal torque requests

Engine startup Idle speed control Engine speed limit Engine protection

Torque

Injection time

Individual cylinder fuel cut-off

Ignition timing

Torque conversion To realize ideal torque

Torque requirements coordinator To coordinate the torque and efficiency requirements

Fig. 2-2 Torque-based M7 System Structure

Comparing with previous M-series engine EFI management system, M7 system mainly features:

 The new engine functional structure of variable torque has strong expandability and is

easily compatible with other systems;

 New modular software structure and hardware structure ensures high portability;  Model based basic characteristics of the engine are mutually independent, which will

simplify the calibration process;

 Camshaft position sensor and sequential fuel injection help to improve the emissions;  Coordinate various torque requirements intensively to improve drivability;  The system can be expanded according to future needs, such as: future emission

regulations, electronic throttle, etc.

Section 2 Control Signal: M7 System I/O Signal

Signals above enter the ECU where they are processed to produce the required actuator control signals. These signals will be amplified in the output drive circuit and transmitted to relevant actuator, as shown below:

Input signals for major ECU sensors in M7 system include:

 Intake pressure signal  Intake temperature signal  Throttle angle signal  Coolant temperature signal  Engine speed signal  Phase signal  Knock sensor signal  Oxygen sensor signal  Vehicle speed signal  A/C pressure signal

 Idle speed stepper motor opening  Fuel injection timing and duration  Fuel pump relay  Carbon canister control valve opening

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 Ignition coil dwell angle and ignition advance angle  A/C compressor relay  Cooling fan relay

Section 3 System Functions

3.1 Start Control Special computing method is required for controlling the charge, fuel injection and ignition timing during start. The air is motionless early in the intake manifold where the pressure is displayed as the ambient atmosphere pressure and designated as a fixed parameter subject to the start temperature by the idle speed stepper motor when the throttle valve is closed. In a similar process,

the specific ―Fuel Injection Timing‖ is designated as an initial injection pulse. The fuel injection

quantity varies with the engine temperature so as to speed up the formation of oil film on the wall of intake manifold and cylinder. Therefore, mixture must be enriched before the engine reaches a certain speed. Once the engine starts running, the system reduces the cranking enrichment immediately and cancels it completely at the end of starting (600…700min-1). Ignition angle is also constantly adjusted under starting condition. Ignition angle is also constantly adjusted under starting condition, and changes with the engine temperature, intake air temperature and engine speed.

3.2 Heater and Three-way Catalytic Converter Heating Control After the engine starts at a low temperature, the cylinder charge, fuel injection and electronic ignition are all adjusted to compensate for higher torque requirements; such process will be lasted until the temperature rises up to an appropriate threshold. In this stage, the most important is to heat the three-way catalytic converter rapidly, as it may greatly reduce the exhaust emission after it starts working. With the ignition advance angle properly delayed, the three-way catalytic converter can be heated by using waste gas in this state.

3.3 Acceleration/Deceleration and Reverse-Towing Fuel Cut-off Control Part of the fuel injected to the intake manifold may not reach the cylinder for subsequent combustion. On the contrary, it forms a layer of oil film on the wall of intake manifold. With the increase of load and the extension of fuel injection time, the fuel stored in the oil film will be increased rapidly. As the throttle opening increases, part of the injected fuel will be absorbed by the oil film. Thus, supplementary fuel must be injected to compensate and avoid mixture enleanment during acceleration. Once the loading factor reduces, the added fuel contained in the fuel film on the wall of intake manifold will be released, so the fuel injection time must be accordingly shortened during deceleration. The towing or reverse towing state refers to the conditions where the power provided for the flywheel by the engine is negative. In this case, engine friction and pumping loss can be used to reduce the vehicle speed. In such a state, the fuel

may be cut off so as to reduce the fuel consumption and exhaust emission, what’s more, to

protect the three-way catalytic converter. Once the engine speed is reduced to a specific one over the idle speed, fuel supply may be restored by the fuel injection system. Actually, a range for speed recovery is contained in the ECU program, which varies with such parameters as engine temperature and dynamic change in engine speed and can prevent the speed from being reduced to the specified minimum threshold by calculation. In case of fuel supply recovery, the fuel injection system starts supplementing fuel with the initial injection pulse and reforms a layer of oil film on the wall of intake manifold. Meanwhile, the torque-based control system will get the engine torque increased slowly and smoothly (smooth transition).

3.4 Idle Speed Control Engine running idle will not provide torque for the flywheel. To ensure stable operation of the engine at the lowest possible idle speed, the closed loop idle speed control system must maintain the balance between the generated torque and "power consumption" of the engine. During idling, certain amount of power must be generated to meet the load requirements. During idling, certain amount of power must be generated to meet the load requirements, including engine crankshaft, valve gear and accessories, e.g. the internal friction of the water pump.

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On the basis of the closed-loop idle speed control, the torque-based control strategy for M7 system determines the engine output torque which is necessary to maintain the required idle speed in any operating conditions. This output torque increases/decreases with the

decrease/increase of engine speed. System responds to new ―interference factor‖ by requiring

greater torque, such as turning on/off of the air-conditioning compressor or shift of automatic transmission. When the engine temperature is much lower, the increase of torque is also required to compensate larger internal friction loss and/or maintain a higher idle speed. The sum of all these output torque requirements will be transferred to the torque coordinator which deals with and computes the requirements and obtains the relevant charging density, mixture ingredient and ignition timing.

3.5  closed-loop Control Exhaust aftertreatment is an effective way to reduce the concentration of harmful substances in the waste gas. The three-way catalytic converter can effectively reduce hydrocarbon (HC), carbon monoxide (CO) and nitrogen oxides (NOx) by 98% or more where they are converted into water (H2O), carbon dioxide (CO2) and nitrogen (N2). Such high efficiency can only be achieved when the engine is operated within a narrow range around the excess air factor =1. The goal of  closed-loop control is to ensure the mixture density is within this range.  closed-loop control system can work only when the oxygen sensor is equipped, which monitors the oxygen contents in the waste gas at the side of three-way catalytic converter. Lean mixture (1) produces about 100mV sensor voltage while the rich mixture produces about 900mV sensor voltage. In case of =1, an abrupt change appears in the sensor voltage.  closed-loop control responds to the input signal (1 indicating too lean mixture and 1 indicating too rich mixture) to modify the control variable and produces a modifying factor which serves as the multiplier to modify the fuel injection duration.

3.6 Evaporative Emission Control For the reason of external radiant heat and oil return heat transfer, the fuel in the fuel tank is heated and becomes a fuel vapor which contains a lot of HC ingredients and thus cannot be directly discharged into the atmosphere according to the Evaporative Emission Standards. In the system, the fuel vapor travels through a duct, then enters the carbon canister and at last is cleaned and blown into the engine for combustion when appropriate. Vapor flow is controlled by ECU only when the  closed-loop control system works under the closed-loop condition.

3.7 Knock Control The knock sensor properly installed in the engine is intended to detect the characteristic vibration when knock occurs, and convert such vibration into electronic signals which will be transmitted to ECU and processed here. Special process algorithm will be used by ECU to check if knock occurs in each cylinder during a combustion cycle. Once knock is detected, knock closed-loop control will be triggered. After knock danger is eliminated, ignition for the affected cylinder will be gradually pushed to the predetermined ignition advance angle again. The threshold of knock control has good adaptability to different conditions and fuels of different grades.

Section 4 Introduction to System Malfunction Diagnosis

4.1 Malfunction Information Records The engine ECU constantly monitors the sensors, the actuators, the relevant circuits, the malfunction indicators, the battery voltage as well as the engine ECU itself and also detects the reliability of the sensor output signals, the actuator drive signals and the internal signals (such as  closed-loop control, coolant temperature, knock control, idle speed control and battery voltage control). In case certain faulty part or unreliable signal value is detected, a malfunction information record will be made immediately by ECU, stored on the RAM memory in the form of DTC and displayed in order of appearance.

11

Function Diagnosis

Data Acquisition

Control Command

Sensor

Actuator

Engine

Fig. 2-3 Schematic Diagram of Troubleshooting EFI System

4.2 Connection of Electric Diagnostic Tester The system uses "K" line communication protocol and ISO 9141-2 standard diagnostic connector, as shown in Fig. 2-4. This standard diagnostic connector is fixedly connected on the engine wiring harness. For the standard diagnostic connector, 4#, 7# and 16# pin are used to diagnose the engine management system (EMS). Pin 4 of the standard diagnostic connector is connected to the ground wire of the car; pin 7 is connected to pin 71 of ECU, i.e. "K" line of engine data; pin 16 is connected to positive terminal of the battery.

Fig. 2-4 ISO9141-2 Standard Diagnostic Connector

Communication between the engine ECU and the external diagnostic tester can be established

with the cable ―K‖ and the following operations can be performed. (See "M7 Electric Diagnostic

Tester Introduction" for the details of function and operation)

Section 5 Description of Related Problems

System features:

Multi-point sequential injection system; The new engine functional structure of variable torque has strong expandability and is easily compatible with other systems; New modular software structure and hardware structure ensures high portability; Use cylinder detection signal (camshaft position sensor); Use signal plate to identify speed signal (crankshaft position sensor); Stepper motor air control; Achieve idle torque closed-loop control; Knock control (knock sensor KS-1-K); Feature catalytic converter heating and protection; Integrate limp home function; Integrate flicker code function

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Part 3 M7 System Component Structure, Principle and Troubleshooting

Section 1 Introduction to Engine Management System Component Layout

473Q engine

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A: Throttle position sensor;

B: Idle speed stepper motor

C: Intake temperature/pressure sensor

G: Knock sensor

H: Crankshaft position sensor

D: Coolant temperature sensor

E: Camshaft position sensor F: Ignition coil

I: Front oxygen sensor

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Intake Air Pressure and Temperature Sensor

J: Carbon canister control valve

Section 2 Intake Air Pressure and Temperature Sensor

Diagrams and pins

Fig. 3-1 Intake Air Pressure and Temperature

Sensor

K: Fuel injector nozzle

L: Engine ECM

Fig. 3-2 Circuit Diagram of Intake Air Pressure

and Temperature Sensor

Fig. 3-3 Intake Pressure and Temperature

Sensor Plug Pin definition: 1# ground; 2# intake temperature signal output; 3# connected to 5V; 4# intake pressure signal output

15

Parameter

Value

Unit Min.

Typ.

Max.

Supply voltage resistance

16

V

Pressure resistance

500

kPa

Storage temperature resistance

-40

+130

C

Parameter

Value

Unit Min.

Typ.

Max.

Range of pressure test

20 115

kPa

Operating temperature

-40 125

C

Voltage of operating power supply

4.5

5.0

5.5 V Current at US = 5.0V

6.0

9.0

12.5

mA

Load current of the output circuit

-0.1 0.1

mA

Load resistance to ground or battery

50

k

Response time

0.2 ms

Weight

27 g

2.1 Installation Position This sensor consists of two sensors i.e. intake manifold absolute pressure sensor and intake air temperature sensor, which are mounted on the intake manifold.

2.2 Principle The sensor element of intake manifold absolute pressure consists of one silicon chip. A pressure diaphragm is etched in the silicon chip. The pressure diaphragm has four piezo resistors, which form a Wheatstone bridge as a strain element. In addition to this pressure diaphragm, the silicon chip also integrates signal processing circuit. The silicon chip and a metal housing form a closed space, in which the absolute pressure of the air within the reference space is close to zero. Thus a microelectronic mechanical system is formed. The active surface of the silicon chip is subject to a pressure near zero, and the back is subject to the intake manifold absolute pressure introduced

through a pipe. The thickness of the silicon chip is only a few micrometers (m), so that the change of intake manifold absolute pressure will cause mechanical deformation of the silicon chip, four piezo resistors deform, and the resistance value also changes. After processed by the signal processing circuit of the silicon chip, the voltage signal which has a linear relationship with the pressure is formed. Intake air temperature sensor element is a negative temperature coefficient (NTC) resistor, which changes with the intake air temperature; this sensor feeds a voltage that represents the intake air temperature changes to the controller.

Fig. 3-4 Sectional View of Intake Manifold Absolute Pressure and Intake Air Temperature Sensor

1. Seal ring, 2. Stainless steel sleeve, 3. PCB board,4. Sensing element, 5. Housing, 6. Pressure holder,7. Welding connection, 8. Adhesive connection

2.3 Technical Characteristics Parameters

2.3.1 Limit data

2.3.2 Characteristic data

16

2.3.3 Transfer function of the pressure sensor UA= (c1 p

abs+c0

) Us In which, UA = signal output voltage (V) US = supply voltage (V) P

= absolute pressure (kPa)

abs

c0=-9.4/95 c1=0.85/95 (1/kPa) It is seen from the above formula that the signal output voltage of the pressure sensor at atmospheric pressure is close to the power supply voltage. If the supply voltage is 5V, the signal output voltage of the pressure sensor when the throttle is fully open is about 4V.

2.3.4 Limit data of temperature sensor Storage temperature: -40 / +130C Carrying capacity at 25C: 100mW

2.3.5 Characteristic data of temperature sensor Operating temperature: -40 / +125C Rated voltage: run with pre-resistor 1 k at 5 V, or with test current 1mA Rated resistance at 20C: 2.5 k 5% The temperature-time coefficient in the air 63, v = 6m/s: 45s

2.4 Installation Considerations The sensor is designed to be installed in the intake manifold plane of the automobile engine. Pressure pipe and temperature sensor are protruding in the intake manifold, and are sealed from the atmosphere with an O-ring. If the sensor is attached to the vehicle in a suitable manner (extracting pressure from the intake manifold, pressure pipe inclining down, etc.), no condensed water will be formed on the pressure-sensitive element. Drilling and fixation on the intake manifold must be carried out in accordance with the supplier drawing, in order to ensure long-term sealing and resistance to the erosion of media. In addition to the impact of part joints, the reliable contact of electrical connection also depends on the material quality and dimensional accuracy of the connector.

2.5 Malfunction and Identification

 Malfunction: flameout, poor idling.  General reasons: 1. Unusual high voltage or reverse current in the process of using; 2.

Vacuum components are damaged in the process of service.

 Service notice: in the process of service, it is prohibited to impact the vacuum components

with high-pressure gas; if any malfunction is discovered and the sensor should be replaced, check whether the generator output voltage and current are normal.

 Simple measuring method:

Temperature sensor: (remove the connector) switch the digital multimeter to Ohm, connect the two meters to 1# pin and 2# pin sensor respectively, the rated resistance at 20°C is 2.5kΩ±5%, and other relevant resistance values can be measured with above characteristic curve. Simulation method can also be used for measurements, that is, supply air to the sensor with a hair dryer (do not get too close), and observe the change in the sensor resistance, which should be decreased.

Pressure sensor: (attach the connector) switch the digital multimeter to DC voltage, connect the black tip to the ground and connect the red tip to 3# pin and 4# pin respectively. In idling state, #3 pin should have a reference voltage of 5V, 4# pin is about 1.3V (specific value depends on model); in no-load state, slowly open the throttle, the voltage of #4 pin doesn’t change significantly; quickly open the throttle, the voltage of #4 pin can reach 4V instantaneously (specific value depends on model) and then decrease to about 1.5V (specific value depends on model).

17

Throttle Position Sensor

Fig. 3-5 NTC Resistance Characteristic Curve

of Intake Temperature Sensor

Section 3 Throttle Position Sensor

Diagrams and pins

Fig. 3-6 Throttle Position Sensor

Fig. 3-7 Circuit Diagram of Throttle Position Sensor

Fig. 3-8 Throttle Position Sensor Connector

Pin definition: 1# connecting to 5V power supply; 2# connecting to ground; 3# connecting to output signal

3.1 Installation Position Mounted in the throttle body.

3.2 Principle

This is an angle sensor with linear output, consisting of two arc-shaped slider resistors and two slider arms. The shaft of the slider arm is connected to the throttle shaft in the same axis. Both ends of the slider resistor are applied with 5V supply voltage US. When the throttle is rotating, the slider arm follows, moves on the slider resistor at the same time, and the contact potential UP is led to output voltage. Therefore, it is actually a corner potentiometer, which outputs voltage signal proportional to the throttle position.

18

3.3 Technical Characteristics Parameters

Parameter

Value

Unit

Mechanical angle between the two limit

positions

95



Available electrical angle between the two

limit positions

86



Permissible slider arm current

18

A

Storage temperature

-40/+130

C

Permissible vibration acceleration

700

m/s2

Parameter

Value

Unit

Min.

Typ.

Max.

Total resistance (terminal 1-2)

1.6

2.0

2.4

k

Slider protection resistor

(Slider at Zero position, terminal 2-3 )

710

1380



Operating temperature

-40 130

C

Power voltage

5

V

Voltage ratio at the right limit position

0.04

0.093

Voltage ratio at the left limit position

0.873

0.960

UP/US increment rate with the increase of

throttle angle

0.00927

1/

Weight

22

25

28

g

(1) Limit data

(2) Characteristic data

3.4 Installation Considerations

 The allowable tightening torque of fastening screws is 1.5Nm~2.5 Nm.

3.5 Malfunction and Identification

 Malfunction: poor acceleration.  General reason: man-made.  Service notice: Note installation position.  Simple measuring method:

(remove the connector) switch the digital multimeter to Ohm, connect the two meters to 1# pin and 2# pin of the sensor respectively, and the resistance under normal temperature is 2kΩ±20%. Connect the two meters to 1# pin and 3# pin respectively, turn the throttle, the resistance changes in linear with the throttle opening, while 2# pin and 3# pin are reverse.

Note: While observing changes in resistance, check whether the resistance value has larger jump.

19

Coolant temperature sensor

Engine ECM

To combination instrument

Section 4 Coolant Temperature Sensor

Diagrams and pins

Fig. 3-9 Coolant Temperature Sensor

Fig. 3-10 Circuit Diagram of Coolant Temperature Sensor

Fig. 3-11 Coolant Temperature Sensor Connector

Pin definition:

Pin A is signal output;

Pin B connects to combination instrument;

Pin C connects to ground;

20

Structure diagram

1. Electrical connector

2. Housing

3. NTC resistor

Resistance

Temperature

4.1 Installation Position Mounted in the engine outlet.

4.2 Principle This sensor is a negative temperature coefficient (NTC) thermistor, the resistance of which decreases with the rise in coolant temperature, but not a linear relationship. The negative temperature coefficient thermistor is mounted on a copper surface, as shown in Fig. 3-12.

Fig. 3-12 Coolant Temperature Sensor Section

Fig. 3-13 Coolant Temperature Sensor Characteristic Curve

21

Parameter

Value

Unit

Rated voltage

Only run with ECU

20Rated resistance at 20C

2.55%

k

Operating temperature

-30~+130

C

Maximum measurement current through

the sensor

1

mA

Permissible vibration acceleration

600

m/s2

No.

Resistance (k)

Temperat

ure

(C)

Temperature Tolerance 1C

Temperature Tolerance 0C

Min.

Max.

Min.

Max.

1

8.16

10.74

8.62

10.28

-10

2

2.27

2.73

2.37

2.63

+20

3

0.290

0.354

0.299

0.345

+80

4.3 Technical Characteristics Parameters

4.3.1 Limit data

4.3.2 Characteristic data

4.4 Installation Considerations The coolant temperature sensor is mounted on the cylinder, and the copper heat sleeve is inserted into the coolant. The sleeve is threaded, and the coolant temperature sensor can be easily screwed into the threaded hole in the cylinder body with the hexagonal head of the sleeve. Permitted maximum tightening torque is 20Nm.

4.5 Malfunction and Identification

 Malfunction: difficult to start  General reason: man-made.  Simple measuring method:

(Remove the connector) switch the digital multimeter to Ohm, connect the two meters to A pin and C pin of the sensor respectively, the rated resistance at 20°C is 2.5kΩ±5%, and other values can be measured with above characteristic curve. Simulation method can also be used for measurements, that is, put the working area of the sensor into boiling water (soak for sufficient time), and observe the change in the sensor resistance, which should decrease to 300Ω-400Ω (specific values depending on water temperature).

Section 5 Knock Sensor

Diagrams and pins

Fig. 3-14 Knock Sensor without Cable

Fig. 3-15 Knock Sensor with Cable

22

Engine ECM

Knock sensor

1. Vibration block

2. Shell

3. Piezoelectric ceramic body

4. Contact

5. Electrical connector

Sensitivity

Frequency

Fig. 3-16 Knock Sensor Circuit Diagram

generated by the vibration of the mass block, the piezoelectric crystal generates voltage in the two pole faces and converts the vibration signal into AC voltage signal output. The frequency response curve is shown in the figure below. Since the frequency of the vibration signal caused by the engine knock is much higher than the frequency of the normal engine vibration signal, the knock signal and non-knock signal can be distinguished after the signals of the knock sensor are processed by the ECU

Fig. 3-17 Knock Sensor Section

Fig. 3-18 Knock Sensor Connector Pin: 1# pin connecting to 19# pin of ECU; 2# pin connecting to 20# pin of ECU.

5.1 Installation Position Mounted on the engine cylinder block

5.2 Principle The knock sensor is a vibration acceleration sensor, which is mounted in the engine cylinder block. One or more sensors are permissible. The sensitive element of the sensor is a piezoelectric element. The vibration of the engine cylinder is passed to the piezoelectric crystals through the mass block within the sensor. Due to the pressure

Fig. 3-19 Knock Sensor Frequency Response

Curve

23

5.3 Technical Characteristics Parameters

Parameter

Value

Unit

Min.

Typ.

Max.

Operating temperature

-40

+130

C

Parameter

Value

Unit

New sensor sensitivity to 5kHz signal

268

mV/g

Linearity between 3 and 15kHz

Linearity at 5kHz  15%

Linearity in resonance

15~39

mV/g

Changes over lifetime

≤-17%

Main resonance frequency

20

kHz

Impedance Resistance

1

M

Capacitance

1200400

pF

Including cable

capacitance

28060

pF/m

Leak resistance

(Resistance between two output terminals

of the sensor)

4.815%

M

Sensitivity change caused by temperature

-0.06

mV/gK

(1) Limit data

(2) Characteristic data

5.4 Installation Considerations The installation position of the knock sensor accepts the vibration signal from all cylinders easily. The modal analysis of the engine block should be used to determine the best installation location of the knock sensor. Do not expose the sensor to any liquid for long time, such as engine oil, coolant, brake fluid and water. Do not use any type of gasket for installation. The sensors must be close to the cylinder block with its metal surface. For wiring of sensor signal cable, do not let the signal cable resonate to avoid breakage. Avoid turning on the high voltage between 1# and 2# pin of the sensor, or else it might damage the piezoelectric element.

5.5 Malfunction and Identification

 Malfunction: poor acceleration.  General reason: a variety of liquids, such as engine oil, coolant, brake fluid, and water

contact the sensor for long time, which will corrode the sensor.

 Service notice: (refer to Installation Considerations)  Simple measuring method:

(remove the connector) switch the digital multimeter to Ohm, connect the two meters to 1# and 2# pin of the sensor respectively, and the resistance under normal temperature should be higher than 1MΩ. Switch the digital multimeter to millivolts, tap in the vicinity of the knock sensor with a hammer, and there should be voltage signal output at this time.

24

Section 6 Oxygen Sensor

EFI main relay

Front oxygen sensor

Rear oxygen sensor

EFI main relay

Diagrams and pins

Fig. 3-20 Oxygen Sensor

Fig. 3-21 Oxygen Sensor Section

1. Cable, 2. Disc washer, 3. Insulating bush, 4. Protective cover, 5. Heating element clamp connector, 6. Heating rod, 7. Contact pad, 8. Sensor block, 9. Ceramic probe, 10. Protection tube

Fig. 3-23 Rear Oxygen Sensor Circuit

Diagram

Fig. 3-24 Front Oxygen Sensor

Connector Pin definition: Front oxygen sensor: 1# pin connecting to the main relay; 2# pin connecting to 48# pin of ECU; 3# pin connecting to 36# pin of ECU; 4# pin connecting to 18# pin of ECU

Fig. 3-22 Front Oxygen Sensor Circuit

Diagram

Fig. 3-25 Rear Oxygen Sensor Connector

Rear oxygen sensor: D pin connecting to the main relay; C pin connecting to 28# pin of ECU; B pin connecting to 55# pin of ECU; A pin connecting to 36# pin of ECU.

25

Parameter

Value

Unit

Min.

Typ.

Max.

Storage temperature

-40 +100

C

Operating

temperatur

e

Ceramic tube end

200 850

C

Hexagon head for housing

570

C

Metal snap ring and

connecting cable

250

C

Connector plug

120

C

Output Voltage

Excess Air Coefficient

6.1 Installation Position Mounted on the exhaust pipe

6.2 Principle The sensing element of the oxygen sensor is a ceramic tube with pore, the outside of the pipe wall is surrounded by the engine exhaust gas, and the inside is connected to the atmosphere. Sensing ceramic pipe wall is a solid electrolyte with electric heating pipe, as shown in Fig. 3-21. The work of the oxygen sensor is achieved by converting the oxygen ion concentration difference inside and outside of the sensing ceramic pipe into voltage signal. When the temperature of the sensing ceramic pipe reaches 350°C, it has the characteristics of solid electrolyte. Because of its special materials, the oxygen ions can freely pass through the ceramic pipe. With this feature, the concentration difference is converted into electrical potential difference, thereby forming an electrical signal output.

Fig. 3-26 600C Oxygen Sensor Characteristic Curves

If the mixture is rich, the oxygen ion concentration difference inside and outside the ceramic pipe is very high, the potential difference is high, a large amount of oxygen ions move from the inside to the outside, and the output voltage is high (800mV-1000mV); if the mixture is lean, the oxygen ion concentration difference inside and outside the ceramic pipe is very low, the potential difference is low, only a small amount of the oxygen ions move from the inside to the outside, and the output voltage is low (about 100mV). The signal voltage has sudden change at the theoretical equivalent air-fuel ratio (λ = 1), as shown in Fig. 3-26.

6.3 Technical Characteristics Parameters

6.3.1 Limit data

26

Max.

permissibl

e

temperatur

e during

turning on

the

heating

element

(at most

10

minutes

each time

and 40

hours in

total)

Bleeding at the end of

ceramic tube

930

C

Hexagon head for housing

630

C

Metal snap ring and

connecting cable

280

C

Permissible temperature change rate at

the end of ceramic tube

100

K/s

Permissible ceramic element temperature

when condensate water exists at the

discharge side

350

C

Permissible

vibration of

housing

Random

(peak)

800

m/s2

Simple harmonic vibration

(Vibration shift)

0.3

mm

Simple harmonic vibration

(Vibration acceleration)

300

m/s2

Uninterrupted direct current at 350C

Absolute

value 10

A

Max. uninterrupted alternating current

when discharge temperature  350C and

f1Hz

20

A

Permissible fuel additive

Unleaded gasoline or 0.15g/L lead

permissible

Engine oil consumption and combustion

Permissible value and data must be

confirmed by the customer through tests of

an appropriate size. Standard:

0.7L/1000km

Parameter

New

After 250-hour bench test

Discharge temperature for

establishment of characteristic data

350C

850C

350C

850C

Sensing element voltage (mV) when

=0.97 (CO=1%)

840±70

710±70

840±80

710±70

Sensing element voltage (mV) when

=1.10

20±50

50±30

20±50

40±40

Internal resistance of sensing

element (k)

 1.0

0.1

1.5

0.3

Response time (ms)

(600mV to 300mV)

<200

<400

Response time (ms)

(300mV to 600mV)

<200

<400

6.3.2 Characteristic data

27

6.3.3 Electric data of sensor

Parameter

Value

Unit

Insulation

resistance between

the new sensor

heating element

and the sensor

connector

Heating element powers off at room

temperature

30

M

Discharge temperature 350C

10

M

Discharge temperature 850C

100

k

Supply voltage on

the plug

Rated voltage

12

V

Uninterrupted working voltage

12~14

V

Working voltage maintained for no

more than 1% of the total service life

(discharge temperature 850C)

15

V

Working voltage maintained for no

more than 75 seconds (discharge

temperature 350C)

24

V

Test voltage

13

V

Heating power when attaining thermal equilibrium under 13V

working voltage

(discharge temperature at 350C; discharge flow rate at

about 0.7 m/s)

12

W

Heating current when attaining thermal equilibrium under

13V working voltage

(discharge temperature at 350C; discharge flow rate at

about 0.7 m/s)

5

A

Fuse wire of heating circuit

8

A

Lead contents in gasoline (g/L)

Service life (km)

0.6

30000

0.4

50000

0.15

80000

0.005 (unleaded gasoline)

160000

6.3.4 Service life The service life of oxygen sensor depends on the lead contents in the gasoline (see the table below).

6.4 Malfunction and Identification

 Malfunction: poor idling, poor acceleration, excessive exhaust, fuel consumption is too high,

etc.

 General reason: 1. moisture enters the sensor, temperature changes suddenly, and the

probe fractures; 2. Oxygen sensor "poisoned" (Pb, S, Br, Si)

 Service notice: Do not use cleaning liquid, oily liquid or volatile solid for the oxygen sensor

during servicing.

 Simple measuring method:

(remove the connector) switch the digital multimeter to Ohm, connect the two meters to 1# (C) and 2# (D) pin of the sensor respectively, and the resistance under normal temperature is 1~6Ω. (Connect to the connector) in idle state, switch the digital multimeter to DC voltage when the oxygen sensor reaches its working temperature of 350℃, connect two meters to 3# (A) and #4 (B) pin of the sensor respectively, and the voltage should fluctuate between 0.1-0.9V quickly at this time.

28

Crankshaft Position Sensor

Engine ECM

Section 7 Crankshaft Position Sensor

Diagrams and pins

Fig. 3-27 Crankshaft Position Sensor

Fig. 3-28 Crankshaft Position Sensor Circuit Diagram

Fig. 3-29 Crankshaft Position Sensor Section

29

Parameter

Value

Unit

Min.

Typ.

Max.

Temper

ature

toleran

ce of PUR

wire

cranksh

aft

position

sensor

(see

the

figure

below)

Coil zone

-40

+150

C

Transition zone

Mixed

C

Wire zone

-40

+120

C

Storage temperature

-20 +50

C

Ambient temperature when not

running

-40

+120

C

Long-term ambient

temperature when running

-40

+120

C

Short-term

ambient

temperature

when running

150 hours

+150

C

380 hours

+140

C

Lifetime in wire

zone

150 hours

+150

C

380 hours

+140

C

1130 hours

+130

C

Fig. 3-30 Crankshaft Position Sensor Connector

1. Shielded cable, 2. Permanent magnet, 3. Sensor housing, 4. Mounting bracket, 5. Winding magnetic core, 6. Coil, 7. Air gap, 8.60-2 ring gear

Pin definition: 1# pin connecting to 15# pin of ECU; 2# pin connecting to 34# pin of ECU.

7.1 Installation Position On the transmission housing

7.2 Principle The crankshaft position sensor and the pulse wheel cooperate to provide engine speed information and crankshaft TDC information in the distributorless ignition system. The crankshaft position sensor consists of a permanent magnet and the coil outside of the magnet. The pulse wheel is mounted on the crankshaft, and rotates with a crankshaft. When the tooth tip passes next to the end portion of the crankshaft position sensor, the pulse wheel made of ferromagnetic material is cutting the magnetic lines of the permanent magnet in the crankshaft position sensor, generates induced voltage in the coil, and outputs as the speed signal

7.3 Technical Characteristics Parameters

7.3.1 Limit data

30

Temper

ature

toleran

ce of H&S

wire

cranksh

aft

position

sensor

(see

the

figure

below)

Coil zone

-40

+150

C

Transition zone

Mixed

C

Wire zone

-40

+130

C

Storage temperature

-20 +50

C

Ambient temperature when not

running

-40

+130

C

Long-term ambient

temperature when running

-40

+130

C

Short-term ambient

temperature when running

+150

C

Lifetime in wire

zone

500 hours

+150

C

200 hours

+160

C

Vibration

resistance of each

plane for 168 hours

20~71Hz

Acceleration 40

m/s2

71~220Hz

Amplitude 0.2

mm

Permissible magnetic strength of external

magnetic field in the opposite direction

2

kA/m

Insulation

resistance (10s,

100V test voltage)

New state

1

M

Usage period ends

100

k

Voltage resistance (1-3s, 1200V AC)

Must not breakdown

Wire zone

Transition zone

Coil zone

Fig. 3-31 Three Temperature Zones of Crankshaft Position Sensor

31

Parameter

Value

Unit

Min.

Typ.

Max.

Resistance between 1# and 2# pin at

20C room temperature

731

860

989



Inductance

310

370

430

mH

Output voltage when the crankshaft

rotates at 416 RPM

1650

mV

Phase sensor

7.3.2 Characteristic data

7.4 Installation Considerations

 Take out the crankshaft position sensor only when it will be mounted onto the car or the test

device soon.

 Mount the crankshaft position sensor by pressing rather than hammering.  M612 bolts are recommended to fix the crankshaft position sensor.  The tightening torque is 82Nm.  The air gap between the crankshaft position sensor and the pulse wheel is 0.8~1.2 mm.

7.5 Malfunction and Identification

 Malfunction: can’t start  General reason: man-made.  Service notice: Mount the speed sensor by pressing rather than hammering during servicing  Simple measuring method:

(Remove the connector) switch the digital multimeter to Ohm, connect the two meters to 1# pin and 2# pin of the sensor respectively, and the resistance at 20℃ is 860Ω±10%. (Connect the connector) switch the digital multimeter to AC voltage, connect the two meters to #1 and #2 pin of the sensor respectively, start the engine, and there should be voltage output. (It is recommended

to check with a car oscilloscope)

Fig. 3-32 Test Waveform Diagram

Section 8 Camshaft Position Sensor

Diagrams and pins

Fig. 3-33 Camshaft Position Sensor

Fig. 3-34 Camshaft Position Sensor Circuit

32

Diagram

Hall Sensor Principle When the current Is passes through the semiconductor flake, the Hall voltage Vh is generated in the right direction of the current; the value is directly proportional to magnetic field induction B (vertical to current Is) and current Is. Hall voltage depends on the changing magnetic field induction intensity B.

Direction of rotation

Phase signal wheel

Output signal

Fig. 3-35 Camshaft Position Sensor Connector

Pin definition: 1# pin connecting to 5V power supply; 2# pin connecting to 79# pin of ECU; 3# connecting to ground

8.1 Installation Position Camshaft cover

8.2 Principle This sensor is used to cooperate with pulse wheel inductive sensor in the occasion without distributor and provide crankshaft phase information to ECU, i.e., to distinguish the compression TDC and exhaust DTC of the crankshaft. The sensor uses the Hall principle: Hall voltage depends on the changing magnetic field induction intensity.

Fig. 3-37 Camshaft Position Sensor Working Diagram (I)

Phase signal wheel

Fig. 3-36 Hall Effect Principle

Fig. 3-38 Camshaft Position Sensor Working Diagram (II)

33

Parameter

Value

Unit

Min.

Typ.

Max.

Ambient temperature

-30

+130

C

Mounting clearance

0.5 1.5

mm

Supply voltage

4.5 24

V

8.3 Technical Characteristics Parameters Limit data

8.4 Installation Considerations The sensor housing only has one hole, which is used for fastening.

8.5 Malfunction and Identification

 Malfunction: excessive emissions, increased fuel consumption, etc.  General reason: man-made.  Simple measuring method:

(Connect the connector) turn on the ignition switch but do not start the engine; switch the digital multimeter to DC voltage, and connect the two meters to 1# and 3# pin of the sensor respectively; ensure that the reference voltage is 5V. Start the engine, and check whether the 2# pin signal is normal with the oscilloscope.

Section 9 Electronic Controller Unit

Fig. 3-39 ECU Outline Drawing

9.1 Installation Position On the side of the passenger compartment

9.2 Principle (1) Functions

• Multi-point sequential injection

• Control ignition

• Idle speed control

• Knock control

• Provide sensor power supply

•  closed-loop control, adaptive

• Control carbon canister control valve

• A/C switch

• Engine malfunction indicator

• Fuel rationing correction

34

• Output of engine speed signal

Terminal

No.

Wire

color Terminal definition

Test condition

Standard

value

1

B/R

2# cylinder ignition coil

Engine is running

—

2 W 3# cylinder ignition coil

Engine is running

—

3

W/B

Ignition grounding

Ignition switch

ACC→ON

<1V

4 W 4# cylinder ignition coil

Engine is running

—

5

L/B

1# cylinder ignition coil

Engine is running

—

6

R/B

2# cylinder fuel injector

Engine is running

—

7 O 3# cylinder fuel injector

Engine is running

—

8 B Engine speed output

Engine is running

—

10

——

Vehicle speed signal output

—

12

R/W

Continuous power supply

Ignition switch

ACC→ON

10-14V

13

B/O

Ignition switch

ACC→ON

10-14V

14

B/W

Main relay

Ignition switch

ACC→ON

<1V

15

W

Crankshaft position sensor side A

Constant

—

16

P/W

Throttle position sensor

Ignition switch

ACC→ON

0-5V

17

B/W

Sensor grounding 1

Ignition switch

ACC→ON

<1V

18 Y Front oxygen sensor

Engine is running

—

19 L Knock sensor side A

Engine is running

—

20

B/W

Knock sensor side B

Engine is running

—

27

R/Y

1# cylinder fuel injector

Engine is running

—

28

B/L

Rear oxygen sensor

Engine is running

—

32

G/W

5V power supply 2

Ignition switch

ACC→ON

5V

34

B

Crankshaft position sensor side B

Engine is running

—

35 G Sensor grounding 3

Ignition switch

ACC→ON

<1V

36

P/L

Sensor grounding 2

Ignition switch

ACC→ON

<1V

37

B/R

Intake pressure sensor

Ignition switch

ACC→ON

<1V

39 W Water temperature sensor

Ignition switch

ACC→ON

—

40

R/Y

Intake temperature sensor

Ignition switch

ACC→ON

—

44 B Unsustained power supply

Ignition switch

ACC→ON

10-14V

45 B Unsustained power supply

Ignition switch

ACC→ON

10-14V

46

R/Y

Carbon canister valve

Engine is running

—

• Vehicle speed signal input

• Malfunction self-diagnosis

• Accept engine load signal

(2) ECU pin definitions:

35

47

Gr/Y

4# cylinder fuel injector

Engine is running

—

48 P Front oxygen sensor

Engine is running

—

50

G

Low speed water tank and A/C

condensing fan relay

Engine is running

—

51

W/B

Electronic grounding 2

Ignition switch

ACC→ON

<1V

53

W/B

Electronic grounding 1

Ignition switch

ACC→ON

<1V

55

G/L

Rear oxygen sensor

Engine is running

—

57

G/B

A/C pressure switch

Ignition switch

ACC→ON

<1V

61

W/B

Power grounding 1

Ignition switch

ACC→ON

<1V

62

P

FCANH

Constant

2.5-3.5V

63 B Unsustained power supply

Ignition switch

ACC→ON

10-14V

64

P/W

Stepper motor phase D

Engine is running

—

65

G/Y

Stepper motor phase A

Engine is running

—

66

P/B

Stepper motor phase B

Engine is running

—

67

Gr/L

Stepper motor phase C

Engine is running

—

68

G/B

High speed water tank fan relay

Engine is running

69

G/R

Fuel pump relay

Engine is running

<1V

70

R/L

A/C allowed

Engine is running

—

71

P/B

Diagnostic K-line

Engine is running

75

Y/R

A/C request

Engine is running

—

76

G/Y

Power steering switch

Engine is running

—

77 B Blower compensation

Engine is running

—

79

Br/B

Crankshaft position sensor

Engine is running

—

80

W/B

Power grounding

Engine is running

—

81

W

F-CANL

Constant

1.5-2.5V

Parameter Value

Unit

Min.

Typ.

Max.

Battery voltage Normal operation

9.0 16.0

V

Limited function

6.0~9.0

16.0~18.

0

V

Limit and

duration of

battery

overvoltage

withstand

26.0V

Retain partial function

and be able to

troubleshoot

60

s

Operating temperature

-40 +70

C

Storage temperature

-40 +90

C

9.3 Technical Characteristics Parameters Limit data

9.4 Installation Considerations

 Note the ESD protection during installation  Pay attention to the protection of plug pins

9.5 Malfunction and Identification

 Malfunction: unstable idle, poor acceleration, can not start, idle speed too high, excessive

exhaust, difficult to start, A/C failure, fuel injector control failure, flame out.

36

接主继

电器

ECU

69

燃油泵继电器

30

86

87

85

配电盒

M

Distributor box

To main relay

Fuel pump relay

Fuel pump

 General reasons: 1. the internal parts of ECU are burned due to electrical overload of the

external device; 2. circuit board corrosion due to water entering ECU.

 Service notice: 1. Do not disassemble ECU at discretion in the servicing process; 2. Please

remove the battery head at least one minute before removing ECU; 3. ECU must be removed and stored properly before welding; 4. Do not install any wires to the ECU line.

 Simple measuring method:

1. (Connect to the connector) use the electric diagnostic tester to read the engine malfunction

record;

2. (Remove the connector) check whether ECU cable is intact, especially whether ECU power

supply and grounding line are normal;

3. Check whether the external sensor works normally, whether the output signal is credible, and

whether the line is intact;

4. Check whether the actuator works properly, and whether the line is intact;

5. Finally, replace ECU and test.

Section 10 Electric Fuel Pump

Diagrams and pins

Fig. 3-40 Electric Fuel Pump

Fig. 3-41 Electric Fuel Pump Circuit Diagram

Fig. 3-42 Electric Fuel Pump Connector Pin definition: 1# pin connecting to ground; 2# pin connecting to combination instrument; 3# pin connecting to combination instrument; 4# pin connecting to fuel pump relay

37

Parameter

Value

Unit

Min.

Typ.

Max.

Operating voltage

8 14

V (DC)

System pressure

350 kPa

Outlet pressure

450

650

kPa

Ambient temperature

(for storage and transportation)

-40 +80

C

Permissible fuel temperature

-30 +70

C

Permissible vibration acceleration

20

m/s2

10.1 Installation Position In the fuel tank

10.2 Principle

The electric fuel pump consists of DC motor, vane pump and cover (integrated with check valve, pressure relief valve and anti-electromagnetic interference components), as shown in Fig. 3-43.

Pump and motor mounted on the same shaft

and sealed in the same enclosure. Pump and motor in the enclosure are full of gasoline around, which is used for cooling and lubrication. The battery supplies power to the electric fuel pump through the fuel pump relay, which connects the circuit of the electric fuel pump only when the engine is started and running. When the engine stops running due to an accident, the fuel pump automatically stops running.

Fig. 3-43 Electric Fuel Pump Section

1. Fuel pump cap 2. Electric motor 3. Oil duct 4. Blade

The maximum pressure of the electric fuel pump outlet is determined by the pressure relief valve between 450 and 650kPa. The pressure of the entire fuel system is determined by the fuel pressure regulator, typically 350kPa.

According to the needs of the engine, the electric fuel pump may have different flow rates. Therefore, the electric fuel pump of a model can not be used in another model.

10.3 Technical Characteristics Parameters

10.3.1 Limit data

38

10.3.2 Characteristic data

The flow of the electric fuel pump is proportional to the voltage under certain fuel pressure.

10.4 Installation Considerations

The electric fuel pump should be stored in sealed original packing box. After mounted on the car, the maximum allowable storage time is six months; as accessories, the maximum storage time is four years. Over this time, manufacturers should re-test the performance data of the fuel pump. On storage sites, the fuel pump must be protected from the influence of the atmosphere. During storage, the original packaging must not be damaged.

When installing the fuel pump, install an inlet strainer with mesh size not greater than 60m or mutually agreed with the client. Do not eject the fuel beam from the vent to inlet strainer, fuel pump holder or fuel tank walls. Be careful when handling the fuel pump. First, it is necessary to protect the fuel inlet strainer from load and impact. Take out the fuel pump from the plastic packaging carefully. The protective cover is removed only when the fuel pump is soon to be installed. Never take out the fuel filter strainer. The foreign matters entering into the fuel pump inlet or strainer will damage the fuel pump.

Keep it clean when install the fuel pipe. The inside of the fuel pipe must be clean. Only use new pipe clip. Make sure that the pipe clip is in the correct position and follow the manufacturer's recommended method. Do not grip the fuel pump at the fuel pipe or inlet strainer. To prevent fuel pump damage, do not run the fuel pump in dry state. Do not use a damaged fuel pump and the fuel pumps that have been dropped to the ground. If the fuel tank falls to the ground, replace the fuel pump in the tank.

In case of goods return, please send back the fuel pump together with the supply order, inspection sheet and packaging label. The returned fuel pumps must be packaged in accordance with the provisions. If the fuel pump has been used, rinse with the test solution and dry in the air. Do not blow the fuel pump to dry.

10.5 Malfunction and Identification

 Malfunction: big noise during running, poor acceleration, can not start (difficult to start), etc.  General reasons: poor quality fuel resulting in: 1. Colloid stacked to form an insulating layer;

2. Pump bushing and armature are locked; 3. Fuel level sensor component is corroded.

 Service notice:

1. According to the needs of the engine, the electric fuel pump may have different flows; the

fuel pumps that have the same shape and can be fitted may not be appropriate; the part number of the fuel pump must be consistent with the original;

2. In order to prevent accidental damage of the fuel pump, do not run for a long time in the

dry state;

3. If the fuel pump needs to be replaced, please clean the fuel tank and piping and replace

the fuel filter.

 Simple measuring method:

(Remove the connector) switch the digital multimeter to Ohm, connect two meters to 1# and 4# pin of the fuel pump respectively, and the resistance between the two pins is about 1Ω.

(Connect the connector) connect the fuel pressure gauge to the inlet pipe, start the engine, and check whether the fuel pump is working; if not, check the whether 4# pin has supply voltage and whether 1# pin is grounded; if running, check whether the fuel pressure is 350kPa in idling state; step on the accelerator until the engine speed reaches 2500rpm, and then check whether the fuel pressure is about 350kPa.

39

Section 11 Fuel Injector

To main relay

1# fuel injector

2# fuel injector

3# fuel injector

4# fuel injector

Diagrams and pins

Fig. 3-44 Fuel Injector

Fig. 3-45 Fuel Injector Circuit Diagram

40

Fig. 3-46 Fuel Injector Connector

Pin definition: This model uses four fuel injectors, and each fuel injector has two pins. Of which, 1# pin is connected to the main relay, and 2# pin is connected to the ECU.

Fig. 3-47 Fuel Injector Section

1. O-ring, 2. Strainer, 3. Fuel injector body with plug, 4. Coil, 5. Spring, 6. valve pin with coil

armature, 7. Valve seat with orifice plate

11.1 Installation Position

On the intake manifold close to the intake valve

11.2 Principle

ECU sends electric pulses to the injector coil to produce magnetic force. When the magnetic force raises enough to overcome the resultant force of return spring pressure, needle valve gravity and frictional force, the needle valve begins to rise and the fuel injection process begins. When the fuel injection pulse ends, the pressure of the return spring makes the needle valve close again.

41

11.3 Technical Characteristics Parameters

Parameter

Value

Unit

Min.

Typ.

Max.

Storage temperature (original package)

-40 +70

C

Permissible fuel injector temperature on

the car

(when not working)

+140

C

Fuel injector

working

temperature

Continuous

-40

+110

C

Short time after hot

starting (about 3

minutes)

+130

C

Permissible fuel

temperature at the

fuel injector inlet

Continuous

+70

C

Short time (about 3

minutes)

+100

C

Temperature where the deviation of fuel

flow reaches 5% compared with 20C

-40 +45

C

Permissible O-ring leak from -35 to -40C

Fuel moist without dripping is allowed in

O-ring area

Permissible maximum vibration

acceleration (peak)

400

m/s2

Supply voltage

6 16

V

Insulation resistance

1

M

Tolerable internal fuel pressure

1100

kPa

Tolerable bending stress

6

Nm

Tolerable axial stress

600

N

Parameter

Value

Unit

Min.

Typ.

Max.

Working pressure (pressure difference)

350

kPa

Fuel injector resistance at 20C

11 17



11.3.1 Limit data

11.3.2 Characteristic data

11.3.3 Allowable fuel The fuel injector can only use the fuel in line with the national standard GB 17930-1999

―Unleaded Gasoline for Motor Vehicles‖ and national environmental protection standards

GWKB 1-1999 ―Hazardous Materials Control Standard for Motor Vehicle Gasoline‖. It should be noted that the gasoline stored for a long time will turn bad. Especially for taxis using LPG and gasoline, LPG is used as fuel for long time, while gasoline is only used to start and the daily consumption of gasoline is few. However, the temperature of the fuel tank is quite high after the fuel pump has been running for long time. The gasoline stored in such fuel tank is very easy to be oxidized and deteriorated, resulting in injector clogging or damage.

11.4 Installation Considerations

 For easy installation, it is recommended to paint silicon-free clean engine oil on the surface

of upper O-ring connected to the fuel distribution pipe. Be careful not to let the engine oil contaminate inside and orifice of the fuel injector.

 Load the fuel injector into the seat vertically, and then fix the fuel injector in the seat with a

clip. Note:

1. The fuel injector clips may be axial or radial; do not misuse.

2. To mount the fuel injector of axial positioning, ensure that the bayonet in the center of the

42

clip is completely clamped into the slot of the fuel injector, and the slots on both sides of the clip are completely clamped into the outer edge of the fuel injector seat.

3. To mount the fuel injector with both axial and radial positioning requirements, use the radial positioning clip, and make the positioning block of the fuel injector and the positioning pins of the fuel injector seat locate in the corresponding slot in the positioning clip respectively.

4. If the fuel injector has two slots, be careful to clamp properly; refer to the original installation location.

 The fuel injector should be installed by hands; do not knock at the fuel injector with a

hammer or other tools.

 O-ring must be replaced when disassemble and re-install the fuel injector. Do not damage

the sealing surface of the fuel injector.

 Do not pull out the support washer of the O-ring from the fuel injector. While installing, avoid

damaging the inlet, O-ring, support ring, orifice plate and electrical plug of the fuel injector. Do not use if there is any damage.

 After installing the fuel injector, test the tightness of the distribution pipe assembly. It is

qualified if there is no leakage.

 The failure parts shall be disassembled by hands. Remove the clip of the fuel injector first,

and then pull out the injector from the seat.

After disassembling, ensure that the fuel injector seat is clean and avoid contamination.

11.5 Malfunction and Identification

 Malfunction: poor idling, poor acceleration, can not start (difficult to start), etc.  General reason: due to lack of maintenance, colloid is accumulated in the fuel injector and

result in failure.

 Service notice: (refer to Installation Considerations)  Simple measuring method:

(Remove the connector) switch the digital multimeter to Ohm, connect the two meters to 1# and 2# pin of the fuel injector respectively, and the resistance between the two pins at 20℃ is 11-17Ω.

Suggestion: Use dedicated cleaning analyzer to clean the fuel injector thoroughly per 20000km.

Section 12 Idle Speed Stepper Motor

Diagrams and pins

Fig. 3-48 Idle Speed Stepper Motor Diagram

43

Idle Speed Stepper Motor

Engine ECM

Fig. 3-49 Idle Speed Stepper Motor Circuit Diagram

Fig. 3-50 Idle Speed Stepper Motor Connector

Pin definition:

Pin A connecting to 65# pin of ECU;

Pin B connecting to 66# pin of ECU; Pin C connecting to 67# pin of ECU; Pin D connecting to 64# pin of ECU.

12.1 Installation Position On the throttle body

12.2 Principle The stepper motor is a miniature motor, which consists of multiple steel stators and one rotor, as shown in Fig. 3-51. Each steel stator is winded with a coil; the rotor is a permanent magnet, and the center of the magnet is a nut. Stator coils are always energized. As long as the current direction of certain coil is changed, the rotor rotates an angle. When the stator coils change the current direction in proper order, a rotating magnetic field is formed, making the rotor made of permanent magnet rotate in a certain direction. If the change of current direction is reversed, the rotation direction of the rotor will also be reversed. The nut connected in the center of the rotor is driven by a screw. Because the screw rod is not designed to be rotated, it can only move in the axial direction, and thus it is also known as a linear axis. The end of the screw rod is a plug, which can retract or extend, thus the cross-sectional area of the idling actuator bypass intake passage is increased or decreased, until it is blocked. Whenever the current direction of a coil is replaced, the rotor rotates for a fixed angle, which is known as the step size, and its value is

equal to 360 divided by the stator or the number of coils. The step size of the stepper motor rotor is 15. Accordingly, the moving distance of every step of the screw rod is also fixed. ECU controls the moving steps of the stepper motor by controlling the number of replacing the coil current direction, and thus adjusts the bypass channel cross-sectional area and the air flow. The air flow rate is substantially a linear relationship with the step length. The plug of the screw rod end has a

44

Linear axis

Rotor sleeve

Housing

Spring washer

O-ring

Compression spring

Front bearing

Dust cover

Axle pin

Rotor

assembly

Rotor core

O-ring

Sleeve bearing

Ball bearing

Rear bearing

Connector

Stator assembly

Cup shell

Polar plate

Bobbin

Electromagne t wire

High pressure

Low pressure

Fuel oil

spring, as shown below. The force that can be used in the elongation direction of the plug equals to the force of the stepper motor plus the spring force; the force available in plug retracting direction equals to the force of the stepper motor minus the spring force.

Fig. 3-51 Idle Speed Stepper Motor Section Diagram

Fig. 3-52 Idle Speed Stepper Motor Installation Diagram

45

Main relay

Ignition coil 1

Ignition coil 4

Ignition coil 2

Ignition coil 3

1# cylinder

2# cylinder

3# cylinder

4# cylinder

Grounding point P1

12.3 Technical Characteristics Parameters

 Install it with two M50.814 bolts.  Bolt tightening torque: 4.00.4Nm.  Install it with spring washers and glue it with binder.  The shaft of idle-speed actuator with a stepper motor shall not be installed into the horizontal

level or lower than that level in order to keep the condensate water out.

 Do not try to push in or pull out the shaft axially by force in any form.

The shaft must be completely retracted before you install the idle-speed actuator with a stepper motor into the throttle body.

12.4 Malfunction and Identification

 Malfunction: idle speed is too high, flame out during idling, etc.  General reasons: the bypass air channel is blocked due to the accumulation of dust, oil and

gas, resulting in abnormal idle adjustment of the stepper motor.

Service notice: 1. Do not apply a force in any form in the axial direction to press in or pull out the shaft; 2. Before installing the idle speed regulator with a stepper motor into the throttle body, its shaft must be in the fully retracted position; 3. Keep the bypass air channel clean.

 Simple measuring method: (remove the connector) switch the digital multimeter to Ohm,

connect the two meters to AD and BC pins of the regulator respectively, and the resistance at 25℃ is 53±5.3Ω.

Section 13 Ignition Coil

Diagrams and pins

Fig. 3-53 Ignition Coil

Fig. 3-54 Ignition Coil Circuit Diagram

46

Parameter

Value

Unit

Min.

Typ.

Max.

Performance

parameters

Operating voltage

6

14

16.5

V

Primary resistance at

20°C

0.70

0.8

0.90



Secondary resistance

at 20°C

9.68

11

12.32

k

Temperature range

-40

+110

℃

F: Ignition coil

Fig. 3-55 Ignition Coil Connector

Pin definition: 1# pin connecting to the main relay; 2# pin connecting to ground; 3# pin connecting to ECU;

13.1 Installation Position Mounted on the engine

13.2 Principle The ignition coil consists of the primary winding, secondary winding, core, and housing. When the ground channel of a primary winding is connected, the primary winding is charged. Once the ECU cuts off the circuit of primary winding, the charging is suspended, and a high voltage is induced in the secondary winding, resulting in discharging of the spark plug.

13.3 Technical Characteristics Parameters Characteristic data

13.4 Malfunction and Identification

 Malfunction: can’t start  General reason: the current is too large, resulting in burning, damage by external force, etc.  Service notice: it is prohibited to test the ignition in ―short-circuit method‖ in the servicing

 Simple measuring method:

(Remove the connector) switch the digital multimeter to Ohm, connect two meters to two pins of the primary winding respectively, the resistance at 20℃ is 0.70-0.90Ω; the resistance of secondary windings is 9.68-12.32kΩ.

process, in order to avoid damage to the electronic controller.

47

To main relay

Carbon canister control valve ∆P is the difference between environmental pressure Pu and intake manifold pressure Ps

Section 14 Carbon Canister Control Valve

Diagrams and pins

Fig. 3-56 Carbon Canister Control Valve

14.2 Principle

Fig. 3-57 Carbon Canister Control Valve

Circuit Diagram

Pin definition:

1# pin connecting to the main relay; 2# pin connecting to 46# pin of ECU

Fig. 3-58 Carbon Canister Control

Valve Connector

14.1 Installation Position On the vacuum pipeline of the carbon canister

- intake manifold

Fig. 3-59 Carbon Canister Control Valve

Section

Fig. 3-60 Carbon Canister Control Valve Installation Diagram

1. From the fuel tank, 2. Carbon canister, 3. Atmosphere, 4. Carbon canister control valve,

5. To the intake manifold, 6. Throttle The carbon canister control valve consists of the electromagnetic coil, armature and valve. The inlet has a strainer. The air flow through the carbon canister control valve depends on the duty cycle of the electrical pulses from ECU to the carbon canister control valve on the one hand, and depends on the pressure difference between the valve inlet and outlet of the carbon canister control valve on the other hand. The carbon canister control valve is closed when there is no electrical pulse.

48

Parameter

Value

Unit

Min.

Typ.

Max.

Operating voltage

9 16

V

1-minute overvoltage

22 V

Min. starting voltage

7

V

Min. voltage drop

1.0

V

Permissible working temperature

-30

+120

C

Permissible short-time working temperature

+130

C

Permissible storage temperature

-40

+130

C

Tolerable inlet and outlet pressure difference

800

mbar

Permissible switching time

108

Permissible vibration acceleration on the

product

300

m/s2

Leakage at 400mbar pressure difference

0.002

m3/h

Parameter

Value

Unit

Min.

Typ.

Max.

Rated voltage

13.5 V

Resistance at +20C

26



Current at the rated voltage

0.5 A

Control pulse frequency

30

Hz

Typical control pulse width

Type A

7

ms

Type B

6

ms

Flow at 200mbar pressure

difference with 100% duty ratio

Type A

2.7

3.0

3.3

m3/h

Type B

1.7

2.0

2.3

m3/h

A type

B type Pressure difference (mbar)

Flow (m3/h)

Different types of carbon canister control valves have different flows at 100% duty cycle, i.e. fully open. Fig. 3-61 shows two typical flow curves. It is seen from the figure that under 200mbar pressure differential, the flow of A-type carbon canister control valve is 3.0m3/h when fully open, and the flow of B-type is 2.0m3/h. (This project uses B type)

Fig. 3-61 Carbon Canister Control Valve Flow Chart

14.3 Technical Characteristics Parameters

14.3.1 Limit data

14.3.2 Characteristic data

49

Parameter

Value

Unit

Min.

Typ.

Max.

Working temperature when the fuel rail is properly

connected with O-ring

-40

+120

C

Max. working temperature within 15 minutes when soaked

+130

C

Max. permissible vibration acceleration peak

300

m/s2

14.4 Installation Considerations The connection of carbon canister control valve, the carbon canister and the intake manifold is shown in Fig. 3-60.

 To avoid transfer of solid sound, it is recommended to mount the carbon canister control

valve on the hose.

 The air flow direction while installing must meet the requirements.  Appropriate measures such as filtration and purification are required to prevent particulates

and other foreign matters entering into the carbon canister control valve from the carbon canister or hose.

 It is recommended to install a protective filter (mesh size < 50m) in the outlet of the carbon

canister.

14.5 Malfunction and Identification

 Malfunction: function unavailable  General reason: foreign objects enter into the valve, resulting in corrosion or poor sealing.  Service notice: 1. The air flow direction while installing must meet the requirements; 2. If the

control valve should be replaced when the valve is invalid due to internal black particles, please check the status of the carbon canister; 3. Avoid water, oil and other liquids entering into the valve in the servicing process; 4. To avoid transfer of solid sound, it is recommended to mount the carbon canister control valve on the hose.

 Simple measuring method:

(Remove the connector) switch the digital multimeter to Ohm, connect the two meters to two pins of the carbon canister control valve respectively, and the resistance at 20℃ is 22-30Ω.

Section 15 Fuel Distribution Pipe Assembly

Diagram

Fig. 3-62 Fuel Distribution Pipe Assembly

15.1 Installation Position On the intake manifold

15.2 Principle Consisting of fuel distribution pipe (KVS) and fuel injector (EV), the fuel distribution pipe assembly is used for fuel storage and distribution.

15.3 Technical Characteristics Parameters Limit data

50

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if the ―Intake Air Pressure‖ in the data

stream is about 101kpa (specific value depends on the air pressure at that time).

Yes

To Step 5

No

Next step

3

Unplug the intake air pressure sensor connector at the end of wire harness, and measure if the voltage between terminal 3# and 1# is about 5V with a multimeter.

Yes

To Step 5

No

Next step

See the characteristic parameters of the pressure regulating valve for the system pressure, refer to the characteristic parameters of the fuel injector for the fuel requirements, and the sealing requires that there is no fuel leakage under the working pressure.

15.4 Installation Considerations

 The inlet tube and rubber tube are clamped tightly with a hoop, the model of which should

match with the rubber tube to ensure that the inlet pipe and rubber tube are sealed.

 There is no crack, scar, groove, burr or rust on inlet pipe wall.  Before assembling the fuel distribution pipe assembly, lubricate the O-ring under the fuel

injector with clean lubricating oil.

15.5 Malfunction and Identification The tightness of the fuel distribution pipe can be tested in the voltage drop method: Test the

O-ring of the fuel injector of the distribution pipe, and the leakage limit at 4.5bar is ≤ 1.5cm3/min.

Part 4 Diagnostic Procedures of Servicing M7 System as per DTC

Note:

1. Conduct the following services only when the malfunction is recognized as steady-state, or

else it will lead to diagnostic mistakes.

2. The multimeter mentioned below is the digital multimeter; it is prohibited to check the EFI

system line with pointer multimeter.

3. For servicing of vehicles with anti-theft system, if the "Follow-up Steps" column indicates to

replace ECU, please program the ECU after replacement.

4. In this project: if DTC P0171, P0172, P0335, P0336 or P1651 exists, engine malfunction

indicator does not light.

5. If the DTC indicates that a circuit voltage is too low, this means that the circuit may be short

circuit to ground; if the DTC indicates that a circuit voltage is too high, the circuit may be short circuit to power supply; if the DTC indicates a circuit failure, the circuit may be broken or a variety of line failures exist. Diagnosis help

1. It is a steady-state malfunction if the DTC can’t be cleared;

For intermittent malfunctions, check whether the harness connector is loose.

2. No abnormalities have been found after check by following the steps mentioned above;

3. Do not neglect the effect of vehicle maintenance, cylinder pressure, and mechanical ignition

timing on the system during servicing;

4. Replace the ECU and make a test.

If the DTC is cleared, the ECU is in trouble; if it still exists, replace with the original ECU and repeat the steps to service it. Below is the service method when each DTC appears: DTC: P0107 ―Circuit voltage of intake air pressure sensor is too low‖

51

4

Check if the lines between pin 17#, 33# and 37# of ECM and the terminal 1#, 3# and 4# of the sensor connector are short to ground.

Yes

Repair or replace the wire harness

No

Next step

5

Start the engine and run idle. Slowly press the accelerator pedal down almost to the floor, and

observe the change of ―Intake Air Pressure‖

displayed on the electric diagnostic tester, which shall not change violently; rapidly press the accelerator pedal down almost to the floor, and the value displayed can reach over 90kpa instantly.

Yes

Diagnosis help

No

Replace the sensor

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if the ―Intake Air Pressure‖ in the data

stream is about 101kpa (specific value depends on the air pressure at that time).

Yes

To Step 5

No

Next step

3

Unplug the intake air pressure sensor connector at the end of wire harness, and measure if the voltage between terminal 3# and 1# is about 5V with a multimeter.

Yes

To Step 5

No

Next step

4

Check if the lines between pin 17#, 33# and 37# of ECM and the terminal 1#, 3# and 4# of the sensor connector are short to ground or power supply.

Yes

Repair or replace the wire harness

No

Next step

5

Start the engine and run idle. Slowly press the accelerator pedal down almost to the floor, and

observe the change of ―Intake Air Pressure‖

displayed on the electric diagnostic tester, which shall not change violently; rapidly press the accelerator pedal down almost to the floor, and the value displayed can reach over 90kpa instantly.

Yes

Diagnosis help

No

Replace the sensor

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if ―Intake Air Temperature‖ in the data

stream is basically equal to the temperature inside the intake-tube (specific value depends on the engine temperature at that time). Note: if the value displayed is often -40°C, broken circuit may exist.

Yes

To Step 5

No

Next step

3

Unplug the wire harness connector from the intake air pressure/temperature sensor and check if the

Yes

Next step

DTC: P0108 ―Circuit voltage of intake air pressure sensor is too high‖

DTC: P0112 ―Indicating temperature of intake air temperature sensor is too low‖

52

resistance between terminal 1# and 2# of the sensor is proportionate to the temperature with a multimeter. (See relevant section of this Manual for details)

No

Replace the sensor

4

Unplug the wire harness connector of the intake air pressure/temperature sensor and measure if the voltage between terminal 1# and 2# is about 5V with a multimeter.

Yes

To Step 5

No

Next step

5

Check if the lines between connector terminal 17# and 40# of ECM and sensor terminal 1# and 2# are broken or short to power supply.

Yes

Repair or replace the wire harness

No

Next step

6

Start the engine and run idle. Observe the change

of ―Intake Air Temperature‖ displayed on the electric

diagnostic tester. Then, the value displayed shall increase with the increase of engine intake air temperature.

Yes

Diagnosis help

No

Replace the sensor

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if ―Intake Air Temperature‖ in the data

stream is basically equal to the temperature inside the intake-tube (specific value depends on the engine temperature at that time). Note: if the value displayed is often -40°C, broken circuit may exist.

Yes

To Step 5

No

Next step

3

Unplug the wire harness connector from the intake air pressure/temperature sensor and check if the resistance between terminal 1# and 2# of the sensor is proportionate to the temperature with a multimeter. (See relevant section of this Manual for details)

Yes

Next step

No

Replace the sensor

5

Check if the lines between pin 17# and 40# of ECM and the terminal 1# and 2# of the sensor connector are short to ground.

Yes

Repair or replace the wire harness

No

Next step

6

Start the engine and run idle. Observe the change

of ―Intake Air Temperature‖ displayed on the electric

diagnostic tester. Then, the value displayed shall increase with the increase of engine intake air temperature.

Yes

Diagnosis help

No

Replace the sensor

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter,

Next step

DTC: P0113 ―Indicating temperature of intake air temperature sensor is too high‖

DTC: P0117 ―Indicating temperature of engine coolant temperature sensor is too low‖

53

and turn the ignition switch to ―ON‖.

2

Observe if ―Coolant Temperature‖ in the data

stream is basically equal to the engine temperature (specific value depends on the engine temperature at that time). Note: if the value displayed is often -40°C, broken circuit may exist.

Yes

To Step 5

No

Next step

3

Unplug the wire harness connector from the coolant temperature sensor and check if the resistance between terminal A# and C# of the sensor is proportionate to the temperature with a multimeter. (See relevant section of this Manual for details)

Yes

Next step

No

Replace the sensor

4

Check if the lines between pin 17# and 39# of ECM and the terminal C# and A# of the sensor connector are short to ground.

Yes

Repair or replace the wire harness

No

Next step

5

Start the engine and run idle. Observe the change of ―Coolant Temperature‖ displayed on the electric diagnostic tester. Then, the value displayed shall increase with the increase of engine coolant temperature.

Yes

Diagnosis help

No

Replace the sensor

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if ―Coolant Temperature‖ in the data

stream is basically equal to the engine temperature (specific value depends on the engine temperature at that time). Note: if the value displayed is often -40°C, broken circuit may exist.

Yes

To Step 5

No

Next step

3

Unplug the wire harness connector from the coolant temperature sensor and check if the resistance between terminal A# and C# of the sensor is proportionate to the temperature with a multimeter. (See relevant section of this Manual for details)

Yes

Next step

No

Replace the sensor

4

Check if the lines between pin 17# and 39# of ECM and the terminal C# and A# of the sensor connector are short to ground.

Yes

Repair or replace the wire harness

No

Next step

5

Start the engine and run idle. Observe the change

of ―Coolant Temperature‖ displayed on the electric

diagnostic tester. Then, the value displayed shall increase with the increase of engine coolant temperature.

Yes

Diagnosis help

No

Replace the sensor

DTC: P0118 ―Indicating temperature of engine coolant temperature sensor is too high‖

54

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if ―Absolute Throttle Opening‖ in the data

stream is within 4%-10% (specific value depends on the model).

Yes

Next step

No

To Step 5

3

Slowly press the accelerator pedal all the way down

to the floor and observe if ―Absolute Throttle Opening‖ in the data stream increases to about

85-95% with the increase of throttle opening (specific value depends on the model).

Yes

Next step

No

To Step 5

4

Repeat Step 3 and observe if ―Absolute Throttle

Opening‖ in the data stream is changed abruptly.

Yes

Replace the sensor

No

Next step

5

Unplug the wire harness connector of the throttle position sensor and check if the lines between the ECU terminal 32#, 35# and 16# and the sensor connector terminal 1#, 2# and 3# are short circuit to ground.

Yes

Repair or replace the wire harness

No

Next step

6

Measure if the voltage between terminal 1# and 2# is about 5V with a multimeter.

Yes

Replace the sensor

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Observe if ―Absolute Throttle Opening‖ in the data

stream is within 4%-10% (specific value depends on the model).

Yes

Next step

No

To Step 5

3

Slowly press the accelerator pedal all the way down

to the floor and observe if ―Absolute Throttle

Opening‖ in the data stream increases to about

85-95% with the increase of throttle opening (specific value depends on the model).

Yes

Next step

No

To Step 5

4

Repeat Step 3 and observe if ―Absolute Throttle

Opening‖ in the data stream is changed abruptly.

Yes

Replace the sensor

No

Next step

5

Unplug the wire harness connector of the throttle position sensor and check if the lines between the ECU terminal 32#, 35# and 16# and the sensor connector terminal 1#, 2# and 3# are short circuit to ground.

Yes

Repair or replace the wire harness

No

Next step

DTC: P0122 ―Circuit voltage of throttle position sensor is too low‖

DTC: P0123 ―Circuit voltage of throttle position sensor is too high‖

55

6

Measure if the voltage between terminal 1# and 2# is about 5V with a multimeter.

Yes

Replace the sensor

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Start the engine and run idle till the coolant temperature reaches the normal level. Observe the

change of ―Oxygen Sensor Voltage‖ displayed on

the electric diagnostic tester where rapid change shall take place between 100mV~900mV.

Yes

Diagnosis help

No

Next step

3

Check if the lines between pin 36# and 18# of ECM and the terminal 3# and 4# of the sensor connector are short to ground.

Yes

Repair or replace the wire harness

No

Next step

4

A. Check the intake air system for severe leakage; B. Check the fuel injector for blockage; C. Check the spark plug for excessive clearance; D. Check the intake valve guide for wear;

Yes

Service it according to the diagnosis

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Start the engine and run idle till the coolant temperature reaches the normal level. Observe the

change of ―Oxygen Sensor Voltage‖ displayed on

the electric diagnostic tester where rapid change shall take place between 100mV~900mV.

Yes

Diagnosis help

No

Next step

3

Check if the lines between pin 36# and 18# of ECM and the terminal 3# and 4# of the sensor connector are short to power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

DTC: P0130 ―Upper oxygen sensor signal circuit malfunction‖

(Note: The diagnosis below applies if P0135 doesn’t occur at the same time; otherwise, please

handle malfunction P0135 first and then follow the procedures below for servicing.)

DTC: P0132 ―Circuit voltage of upper oxygen sensor is too high‖

(Note: The diagnosis below applies if P0135 doesn’t occur at the same time; otherwise, please

handle malfunction P0135 first and then follow the procedures below for servicing.)

56

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Start the engine and run idle till the coolant temperature reaches the normal level. Observe the

change of ―Oxygen Sensor Voltage‖ displayed on

the electric diagnostic tester where rapid change shall take place between 100mV~900mV.

Yes

Diagnosis help

No

Next step

3

Check if the lines between pin 36# and 18# of ECM and the terminal 3# and 4# of the sensor connector are broken.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to ON.

Next step

2

Unplug the wire harness connector of the oxygen sensor and measure if the voltage between terminal 1# and 2# is about 12V with a multimeter.

Yes

Next step

No

To Step 4

3

Check if the resistance between oxygen sensor terminal 1# and 2# is 2~5Ω at 20°C.

Yes

Next step

No

Replace the sensor

4

Check whether 5A fuse in oxygen sensor heating circuit is blown out.

Yes

Replace the fuse

No

Next step

5

Check if the lines between connector terminal 48# and 85# of ECM and sensor terminal 2# and 1# are broken or short to power supply/ground.

Yes

Repair or replace the wire harness

No

Diagnosis help

DTC: P0134 ―Upper oxygen sensor signal malfunction‖ (Note: The diagnosis below applies if P0135 doesn’t occur at the same time; otherwise, please

handle malfunction P0135 first and then follow the procedures below for servicing.)

DTC: P0135 ―Upper oxygen sensor heating circuit malfunction‖

DTC: P0171 ―Air-fuel ratio closed-loop control self-adaption exceeds upper limit‖

(Note: the following diagnostic procedures are applicable to the conditions where DTCs of such parts as intake air pressure sensor, carbon canister control valve and oxygen sensor do not occur simultaneously; if DTCs exist simultaneously, please handle other malfunctions first and then follow the procedures below for servicing.)

57

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Start the engine and run idle till the coolant temperature reaches the normal level.

In all conditions, observe the change of ―Oxygen Sensor Voltage‖ displayed on the electric diagnostic

tester where the value shall remain near 100 mV for a long time under certain working conditions.

Yes

Next step

No

Diagnosis help

3

Connect the fuel pressure gauge to the oil inlet end of the fuel system and observe if the oil pressure is kept at about 350kPa in all conditions.

Yes

Next step

No

Service the fuel system

4

Check if the lines between pin 36# and 18# of ECM and the terminal 3# and 4# of the sensor connector are short to power supply.

Yes

Repair or replace the wire harness

No

Next step

5

A. Check the intake air system for severe leakage; B. Check the fuel injector for blockage; C. Check the spark plug for excessive clearance; D. Check the intake valve guide for wear;

Yes

Service it according to the diagnosis

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Start the engine and run idle till the coolant temperature reaches the normal level.

In all conditions, observe the change of ―Oxygen Sensor Voltage‖ displayed on the electric diagnostic

tester where the value shall remain near 900 mV for a long time under certain working conditions.

Yes

Next step

No

Diagnosis help

3

Connect the fuel pressure gauge to the oil inlet end of the fuel system and observe if the oil pressure is kept at about 350kPa in all conditions.

Yes

Next step

No

Service the fuel system

4

Check if the lines between pin 36# and 18# of ECM and the terminal 3# and 4# of the sensor connector are short to power supply.

Yes

Repair or replace the wire harness

No

Next step

DTC: P0172 ―Air-fuel ratio closed-loop control self-adaption exceeds lower limit‖ (Note: the following diagnostic procedures are applicable to the conditions where DTCs of such parts as intake air pressure sensor, carbon canister control valve and oxygen sensor do not occur simultaneously; if DTCs exist simultaneously, please handle other malfunctions first and then follow the procedures below for servicing.)

58

5

A. Check the fuel injector for leakage; B. Check the bleeding pipe for leakage; C. Check for correct ignition timing;

Yes

Service it according to the diagnosis

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to ON.

Next step

2

Unplug the wire harness connector of the first cylinder fuel injector and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the line between the first cylinder fuel injector connector terminal 1# and the main relay is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2# of first cylinder fuel injector at 20°C is within 11~13O with a multimeter.

Yes

Next step

No

Replace the fuel injector

5

Check if the voltage between the terminal 2# of first

cylinder’s fuel injector and the negative pole of

power supply is about 3.7V with a multimeter.

Yes

Diagnosis help

No

Next step

6

Check if the line between terminal 2 of the first

cylinder’s fuel injector connector and terminal 27#

is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to ON.

Next step

2

Unplug the wire harness connector of the second cylinder fuel injector and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the line between the second cylinder fuel injector connector terminal 1# and the main relay is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2# of second cylinder fuel injector at 20°C is within 11~13Ω with a multimeter.

Yes

Next step

No

Replace the fuel injector

DTC: P0201 ―First cylinder fuel injector circuit malfunction‖

DTC: P0202 ―Second cylinder’s fuel injector circuit malfunction‖

59

5

Check if the voltage between the terminal 2# of

second cylinder’s fuel injector and the negative pole

of power supply is about 3.7V with a multimeter.

Yes

Diagnosis help

No

Next step

6

Check if the line between terminal 2# of the second

cylinder’s fuel injector connector and terminal 6# is

broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to ON.

Next step

2

Unplug the wire harness connector of the third cylinder fuel injector and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the line between the third cylinder fuel injector connector terminal 1# and the main relay is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2# of third cylinder fuel injector at 20°C is within 11~13Ω with a multimeter.

Yes

Next step

No

Replace the fuel injector

5

Check if the voltage between the terminal 2# of

third cylinder’s fuel injector and the negative pole of

power supply is about 3.7V with a multimeter.

Yes

Diagnosis help

No

Next step

6

Check if the line between terminal 2# of the third

cylinder’s fuel injector connector and terminal 7# is

broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to ON.

Next step

2

Unplug the wire harness connector of the fourth cylinder fuel injector and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the line between the fourth cylinder fuel injector connector terminal 1# and the main relay is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2#

Yes

Next step

DTC: P0203 ―Third cylinder’s fuel injector circuit malfunction‖

DTC: P0204 ―Fourth cylinder’s fuel injector circuit malfunction‖

60

of fourth cylinder fuel injector at 20°C is within 11~13Ω with a multimeter.

No

Replace the fuel injector

5

Check if the voltage between the terminal 2# of

fourth cylinder’s fuel injector and the negative pole

of power supply is about 3.7V with a multimeter.

Yes

Diagnosis help

No

Next step

6

Check if the line between terminal 2# of the fourth

cylinder’s fuel injector connector and terminal 47#

is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Unplug the fuel pump relay, turn the ignition switch to ―ON‖ and check if the voltage between 30# and 87# pin of the fuel pump relay and the negative pole of power supply is about 12V respectively.

Yes

To Step 4

No

Next step

3

Check if the line at the power supply end of relay is broken or short to ground.

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the voltage between 85# pin of fuel pump relay and the negative pole of power supply is about 3.7V with a multimeter.

Yes

Replace fuel pump relay

No

Next step

5

Check if the line between the relay pin 85# and the ECU pin 69# is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Unplug the knock sensor connector at the end of wire harness and check if the resistance between

its terminal 1# and 2# is larger than 1MΩ with a

multimeter.

Yes

Next step

No

Replace the sensor

3

Check if the lines between terminal 1# and 2# of the knock sensor connector and terminal 19# and 20# of ECU are broken or short to ground/power supply respectively.

Yes

Repair or replace the wire harness

No

Next step

DTC: P0230 ―Fuel pump control circuit malfunction‖

DTC: P0325 ―Knock sensor circuit malfunction‖

61

4

Replace the knock sensor in accordance with the procedure and put the engine to a trial running over 2200RPM. Check if DTC P0325 occurs again.

Yes

Diagnosis help

No

Check for random failure

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Unplug the crankshaft position sensor connector at the end of wire harness and check if the resistance between its terminal 1# and 2# at 20°C is within 770~950Ω with a multimeter.

Yes

Next step

No

Replace the sensor

3

Check if the lines between terminal 1# and 2# of the knock sensor connector and terminal 15# and 34# of ECU are broken or short to ground/power supply respectively.

Yes

Repair or replace the wire harness

No

Next step

4

Check if the flywheel signal panel is good.

Yes

Diagnosis help

No

Replace the signal panel

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Unplug the crankshaft position sensor connector at the end of wire harness and check if the resistance between its terminal 1# and 2# at 20°C is within 770~950Ω with a multimeter.

Yes

Next step

No

Replace the sensor

3

Check if the lines between terminal 1# and 2# of the knock sensor connector and terminal 15# and 34# of ECU are broken or short to ground/power supply respectively.

Yes

Repair or replace the wire harness

No

Next step

4

Check if the flywheel signal panel is good.

Yes

Diagnosis help

No

Replace the signal panel

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

DTC: P0335 ―Crankshaft position sensor signal malfunction‖

DTC: P0336 ―Crankshaft position sensor signal unreasonable malfunction‖

DTC: P0340 ―Camshaft position sensor signal malfunction‖

62

2

Unplug the camshaft position sensor connector at the end of wire harness and check if the voltage between its terminal 1# of the camshaft position sensor and the negative pole of the power supply is about 5V with a multimeter.

Yes

Go to Step 4

No

Next step

3

Check if the line between camshaft position sensor terminal 1# and ECU 32# is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

Next step

4

Check if the line between terminal 2# and 3# of the camshaft position sensor connector and terminal 79# and 35# of ECU is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Next step

5

Check if the camshaft signal panel is good.

Yes

Diagnosis help

No

Replace the signal panel

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Unplug the camshaft position sensor connector at the end of wire harness and check if the voltage between its terminal 1# of the camshaft position sensor and the negative pole of the power supply is about 5V with a multimeter.

Yes

Go to Step 4

No

Next step

3

Check if the line between camshaft position sensor terminal 1# and ECU 32# is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

Next step

4

Check if the line between terminal 2# and 3# of the camshaft position sensor connector and terminal 79# and 35# of ECU is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Next step

5

Check if the camshaft signal panel is good.

Yes

Diagnosis help

No

Replace the signal panel

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter,

Next step

DTC: P0342 ―Circuit voltage of camshaft position sensor is too low‖

DTC: P0343 ―Circuit voltage of camshaft position sensor is too high‖

63

and turn the ignition switch to ―ON‖.

2

Unplug the camshaft position sensor connector at the end of wire harness and check if the voltage between its terminal 1# of the camshaft position sensor and the negative pole of the power supply is about 5V with a multimeter.

Yes

Go to Step 4

No

Next step

3

Check if the line between camshaft position sensor terminal 1# and ECU 32# is broken or short circuit to ground.

Yes

Repair or replace the wire harness

No

Next step

4

Check if the line between terminal 2# and 3# of the camshaft position sensor connector and terminal 79# and 35# of ECU is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Next step

5

Check if the camshaft signal panel is good.

Yes

Diagnosis help

No

Replace the signal panel

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Unplug the wire harness connector of the carbon canister control valve and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the lines between terminal 1# of carbon canister control valve and main relay terminal 87# are broken or short circuit to ground;

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2# of carbon canister control valve at 20°C is within 22~30Ω with a multimeter.

Yes

Next step

No

Replace the control valve

5

Check if the line between terminal 2# of the carbon canister control valve and ECU terminal 46# is broken.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter,

Next step

DTC: P0443 ―Carbon canister control valve driving control circuit malfunction‖

DTC: P0444 ―Carbon canister control valve driving control circuit voltage is too low‖

64

and turn the ignition switch to ―ON‖.

2

Unplug the wire harness connector of the carbon canister control valve and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the lines between terminal 1# of carbon canister control valve and main relay terminal 87# are broken or short circuit to ground;

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2# of carbon canister control valve at 20°C is within 22~30Ω with a multimeter.

Yes

Next step

No

Replace the control valve

5

Check if the line between terminal 2# of the carbon canister control valve and ECU terminal 46# is short circuit to ground.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Unplug the wire harness connector of the carbon canister control valve and check if the voltage between its terminal 1# and the negative pole of power supply is about 12V with a multimeter.

Yes

To Step 4

No

Next step

3

Check if the lines between terminal 1# of carbon canister control valve and main relay terminal 87# are broken or short circuit to ground;

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the resistance between terminal 1# and 2# of carbon canister control valve at 20°C is within 22~30Ω with a multimeter.

Yes

Next step

No

Replace the control valve

6

Check if the line between terminal 2# of the carbon canister control valve and ECU terminal 46# is short circuit to power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

DTC: P0445 ―Carbon canister control valve driving control circuit voltage is too high‖

DTC: P0480 ―A/C condenser cooling fan relay control circuit malfunction‖

65

2

Unplug A/C condenser cooling fan relay, turn the

ignition switch to ―ON‖ and check if the voltage

between relay terminal 13.61kg and 39.01kg and the negative pole of power supply is about 12V.

Yes

To Step 4

No

Next step

3

Check if the line at the power supply end of A/C condenser cooling fan relay is broken or short to ground.

Yes

Repair or replace the wire harness

No

To Step 2

4

Check if the voltage between 85# pin of A/C condenser cooling fan relay and the negative pole of power supply is about 3.7V with a multimeter.

Yes

Replace the relay

No

Next step

5

Check if the line between the relay pin 85# and the ECU pin 50# is broken or short to ground/power supply.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

If the vehicle is equipped with ABS system, please check whether the ABS system has DTC.

Yes

Service ABS system

No

Next step

3

Check if the speedometer pointers work normally.

Yes

Next step

No

Service instrument line

4

Check if the vehicle speed sensor work normally.

Yes

Next step

No

Replace the vehicle speed sensor

4

Check if the line between vehicle speed sensor signal cable and 59# pin to ECU is broken or short to power supply or ground.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Check if the throttle adjusting screw, throttle cable

Yes

Next step

DTC: P0500 ―Vehicle speed signal unreasonable malfunction‖

DTC: P0506 ―Idle speed is lower than target idle speed‖

66

and throttle conditions work normally.

No

Conduct necessary servicing and maintenance

3

Check if the idle speed stepper motor works normally.

Yes

Next step

No

Conduct necessary servicing and maintenance

4

A. Check the fuel system for too low pressure; B. Check the fuel injector for blockage; C. Check for unsmooth system discharge.

Yes

Conduct necessary servicing

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Check if the throttle adjusting screw, throttle cable and throttle conditions work normally.

Yes

Next step

No

Conduct necessary servicing and maintenance

3

Check if the idle speed stepper motor works normally.

Yes

Next step

No

Conduct necessary servicing and maintenance

4

A. Check the system for leakage; B. Check the fuel injector for leakage; C. Check the fuel system for too high pressure;

Yes

Conduct necessary servicing

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Unplug the idle speed stepper motor connector at the end of wire harness and check if the resistance between its terminal A and D as well as B and C at

20°C is about 53±5.3Ω respectively with a

multimeter.

Yes

Next step

No

Replace the stepper motor

DTC: P0507 ―Idle speed is higher than target idle speed‖

DTC: P0508 ―Idle speed stepper motor control circuit voltage is too low‖

67

3

Check if the lines between terminal A, B, C, and D of the idle speed stepper motor connector and terminal 65#, 66#, 67# and 64# of ECU connector are short to ground.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Unplug the idle speed stepper motor connector at the end of wire harness and check if the resistance between its terminal A and D as well as B and C at 20°C is about 53±5.3Ω respectively with a multimeter.

Yes

Next step

No

Replace the stepper motor

3

Check if the lines between terminal A, B, C, and D of the idle speed stepper motor connector and terminal 65#, 66#, 67# and 64# of ECU connector are short to ground.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Unplug the idle speed stepper motor connector at the end of wire harness and check if the resistance between its terminal A and D as well as B and C at

20°C is about 53±5.3Ω respectively with a

multimeter.

Yes

Next step

No

Replace the stepper motor

3

Check if the lines between terminal A, B, C, and D of the idle speed stepper motor connector and terminal 65#, 66#, 67# and 64# of ECU connector are short to ground.

Yes

Repair or replace the wire harness

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Check if the battery voltage is about 12V with a multimeter.

Yes

Next step

No

Replace the battery

DTC: P0509 ―Idle speed stepper motor control circuit voltage is too high‖

DTC: P0511 ―Idle speed stepper motor control circuit malfunction‖

DTC: P0560 ―System voltage signal unreasonable‖

68

3

Check if the lines between terminal 44#, 45# and 63# of ECU and terminal 87# of main relay are broken or short to ground.

Yes

Repair or replace the wire harness

No

Next step

4

Start the engine and check if the charging voltage of generator is within 9~16V at different speeds.

Yes

Next step

No

Replace the generator

5

Check if the ground point of engine wire harness is good.

Yes

Diagnosis help

No

Repair or replace the wire harness

No.

Operating Steps

Test Result

Follow-up

Steps

1

Turn the ignition switch to OFF.

Next step

2

Check if the battery voltage is about 12V with a multimeter.

Yes

Next step

No

Replace the battery

3

Check if the lines between terminal 44#, 45# and 63# of ECU and terminal 87# of main relay for excessive resistance.

Yes

Repair or replace the wire harness

No

Next step

4

Start the engine and check if the charging voltage of generator is within 9~16V at different speeds.

Yes

Next step

No

Replace the generator

5

Check if the ground point of engine wire harness is good.

Yes

Diagnosis help

No

Repair or replace the wire harness

No.

Operating Steps

Test

Result

Follow-up Steps

1

Turn the ignition switch to OFF.

Next step

2

Check if the battery voltage is about 12V with a multimeter.

Yes

Next step

No

Replace the battery

3

Start the engine and check if the charging voltage of generator is within 9~16V at different speeds.

Yes

Next step

No

Replace the generator

4

Check if the ground point of engine wire harness is good.

Yes

Diagnosis help

No

Repair or replace the wire harness

DTC: P0562 ―System voltage is too low‖

DTC: P0563 ―System voltage is too high‖

69

DTC: P0601 ―ECU check code error‖

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Clear the DTC and check if the malfunction is a steady-state one.

Yes

Next step

No

System is normal

3

Replace the ECU.

End

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Clear the DTC and check if the malfunction is a steady-state one.

Yes

Next step

No

System is normal

3

Replace the ECU.

End

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the electric diagnostic tester and adapter, and turn the ignition switch to ―ON‖.

Next step

2

Conduct an action test to the engine malfunction

indicator with the ―Actuator Action Test‖ on the

electric diagnostic tester and observe if the indicator is always on or off.

Yes

Next step

No

System is normal

3

Check if the line at the power supply end of engine malfunction indicator is broken or short to ground.

Yes

Repair or replace the wire harness

No

Next step

4

Check if the line between control terminal of engine malfunction indicator and terminal 31# of ECU connector is broken or short to power supply or ground.

Yes

Repair or replace the wire harness

No

Next step

5

Check if the engine malfunction indicator works normally.

Yes

Diagnosis help

No

Replace the lamp

DTC: P0602 ―ECU diagnostic data ID error‖

DTC: P1651 ―Engine malfunction indicator (SVS) control circuit malfunction‖

70

No.

Operating Steps

Test Result

Follow-up

Steps

Part 5 Diagnostic Procedures of Servicing M7 System as per Symptoms of Malfunction

Preliminary check shall be made before troubleshooting as per the symptoms of malfunction:

1. Ensure the engine malfunction indicator works normally;

2. Check with the electric diagnostic tester to ensure no malfunction record.

3. Confirm the symptoms of malfunction complained by the owner of car exist and verify the

conditions where such malfunction occurs. Then, visual inspection shall be made:

1. Check the fuel pipeline for leakage;

2. Check the vacuum pipeline for breakage, twist and improper connection;

3. Check the intake air pipeline for blockage, leakage, compression or damage;

4. Check the high tension wire of ignition system for breakage, ageing and wrong ignition order;

5. Check the ground point of wire harness for dirt and looseness;

6. Check the connectors of sensors and actuators for looseness or poor contact.

Important Notice: If the symptoms mentioned above exist, maintenance and repair shall be made against such malfunction; otherwise, the subsequent troubleshooting may be affected. Diagnosis help

1. Confirm there is no engine malfunction record;

2. Confirm the symptoms of complained malfunction exist;

3. No abnormalities have been found after check by following the steps mentioned above;

4. Do not neglect the effect of vehicle maintenance, cylinder pressure, ignition timing and

fuel on the system during servicing;

5. Replace the ECU and make a test.

If the malfunction disappears, the ECU is in trouble; if it still exists, replace with the original ECU and repeat the steps to service it.

1. Engine running slowly or not running when started

2. Engine cannot be started with starter running

3. Hard to start when the engine is hot

4. Hard to start when the engine is cold

5. Hard to start at normal engine speed any time

6. Engine normally started, yet idling unstable any time

7. Engine normally started, idling unstable during heating

8. Engine normally started, yet idling unstable after heating

9. Engine normally started, yet idling unstable or stalling under partial load (e.g. A/C turned on)

10. Engine normally started, yet idling at a higher speed

11. Engine running slowly or stalling during acceleration

12. Slow response in acceleration

13. Sluggish acceleration and poor performance

Section 1 Engine Running Slowly or Not Running When Started

General faulty parts:

1. Battery; 2. Start motor; 3. Wire harness or ignition switch; 4. Engine mechanical part.

General diagnostic flow:

71

1

Check if the voltage between two terminals of battery is about 8~12V with a multimeter when the engine is started.

Yes

Next step

No

Replace battery

2

Keep the ignition switch at the starting position and check if positive terminal of start motor has an over 8V voltage with a multimeter.

Yes

Next step

No

Repair or replace the wire harness

3

Remove the start motor and check its working condition. Check if it is broken or stuck due to poor lubrication.

Yes

Repair or replace the start motor

No

Next step

4

If the malfunction only occurs in winter, check if excessive resistance is caused to the start motor because improper engine lubricant and gear box oil are selected.

Yes

Replace with lubricant of proper class

No

Next step

5

Check if the excessive mechanical resistance inside the engine causes the start motor not to rotate or rotate slowly.

Yes

Service the internal resistance of engine

No

Diagnosis help

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

2

Connect the diagnostic tester for EFI system,

observe the data item ―Engine Speed‖, start the

engine and observe if there is speed signal output.

Yes

Next step

No

Service the crankshaft position sensor line

3

Pull out an ignition coil from one cylinder, connect a spark plug and keep its electrodes about 5mm away from the engine body, start the engine and check for blue high-pressure fire.

Yes

Next step

No

Service the ignition system

Section 2 Engine Cannot Be Started with Starter Running

General faulty parts:

1. Fuel tank without fuel; 2. Fuel pump; 3. Crankshaft position sensor; 4. Ignition coil; 5. Engine

mechanical part. General diagnostic flow:

72

4

Check the pressure of all engine cylinders and observe the engine cylinder for insufficient pressure.

Yes

Troubleshoot the engine mechanical malfunction

No

Next step

5

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

2

Pull out an ignition coil from one cylinder, connect a spark plug and keep its electrodes about 5mm away from the engine body, start the engine and check for blue high-pressure fire.

Yes

Next step

No

Service the ignition system

3

Unplug the connector of coolant temperature sensor, start the engine and observe if it starts successfully. (Or replace the coolant temperature

sensor with a 300Ω resistor to be connected in

series and then observe if the engine starts successfully.)

Yes

Service the line or replace the sensor

No

Next step

4

Check if the electric fuel pump is damaged

Yes

Check or replace

No

Next step

5

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

6

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

Section 3 Hard to Start When the Engine Is Hot

General faulty parts:

1. Fuel with water; 2. Fuel pump; 3. Coolant temperature sensor; 4. Fuel pressure regulator

vacuum tube; 5. Ignition coil. General diagnostic flow:

73

No.

Operating Steps

Test Result

Follow-up

Steps

1

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

2

Pull out an ignition coil from one cylinder, connect a spark plug and keep its electrodes about 5mm away from the engine body, start the engine and check for blue high-pressure fire.

Yes

Next step

No

Service the ignition system

3

Unplug the connector of coolant temperature sensor, start the engine and observe if it starts successfully. (Or replace the coolant temperature

sensor with a 2500Ω resistor to be connected in

series and then observe if the engine starts successfully.)

Yes

Service the line or replace the sensor

No

Next step

4

Press the accelerator pedal down gently and observe if it is easy to start.

Yes

Clean the throttle valve and the idle speed air duct

No

Next step

5

Remove the fuel injector and check it for leakage or blockage with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

6

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

7

Check the pressure of all engine cylinders and observe the engine cylinder for insufficient pressure.

Yes

Troubleshoot the engine mechanical malfunction

No

Next step

8

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

Section 4 Hard to Start When Engine Is Cold

General faulty parts:

1. Fuel with water; 2. Fuel pump; 3. Coolant temperature sensor; 4. Fuel injector; 5. Ignition coil; 6.

Throttle body and idle speed bypass air duct; 7. Engine mechanical part. General diagnostic flow:

74

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check the air filter for blockage and the air intake duct for air leakage.

Yes

Service the air intake system

No

Next step

2

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

3

Pull out an ignition coil from one cylinder, connect a spark plug and keep its electrodes about 5mm away from the engine body, start the engine and check for blue high-pressure fire.

Yes

Next step

No

Service the ignition system

4

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

5

Unplug the connector of coolant temperature sensor, start the engine and observe if it starts successfully.

Yes

Service the line or replace the sensor

No

Next step

6

Press the accelerator pedal down gently and observe if it is easy to start.

Yes

Clean the throttle valve and the idle speed air duct

No

Next step

7

Remove the fuel injector and check it for leakage or blockage with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

8

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

9

Check the pressure of all engine cylinders and observe the engine cylinder for insufficient pressure.

Yes

Troubleshoot the engine mechanical malfunction

No

Next step

10

Check if the ignition order and ignition timing of the

Yes

Next step

Section 5 Hard to Start at Normal Engine Speed Any Time

General faulty parts:

1. Fuel with water; 2. Fuel pump; 3. Coolant temperature sensor; 4. Fuel injector; 5. Ignition coil; 6.

Throttle body and idle speed bypass air duct; 7. Air intake duct; 8. Ignition timing; 9. Spark plug;

10. Engine mechanical part.

General diagnostic flow:

75

engine meet the specifications.

No

Service the ignition timing

11

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check the air filter for blockage and the air intake duct for air leakage.

Yes

Service the air intake system

No

Next step

2

Check if the idle speed stepper motor is blocked.

Yes

Clean or replace

No

Next step

3

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

4

Check the throttle body and idle speed bypass air duct for carbon deposition.

Yes

Clean

No

Next step

5

Remove the fuel injector and check it for leakage, blockage or poor flow with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

6

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

7

Check the pressure of all engine cylinders and observe if it varies greatly.

Yes

Troubleshoot the engine mechanical malfunction

No

Next step

8

Check if the ignition order and ignition timing of the engine meet the specifications.

Yes

Next step

No

Service the ignition timing

9

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

Section 6 Engine Normally Started, yet Idling Unstable Any Time

General faulty parts:

1. Fuel with water; 2. Fuel injector; 3. Spark plug; 4. Throttle body and idle speed bypass air duct;

5. Air intake duct; 6. Idle speed stepper motor; 7. Ignition timing; 8. Spark plug; 9. Engine

mechanical part. General diagnostic flow:

76

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check the air filter for blockage and the air intake duct for air leakage.

Yes

Service the air intake system

No

Next step

2

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

3

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

4

Unplug the connector of coolant temperature sensor, start the engine and observe if unstable idling occurs when the engine is heated.

Yes

Service the line or replace the sensor

No

Next step

5

Remove the fuel injector and check it for leakage, blockage or poor flow with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

6

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

7

Check the pressure of all engine cylinders and observe if it varies greatly.

Yes

Troubleshoot the engine mechanical malfunction

No

Next step

8

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

Section 7 Engine Normally Started, Idling Unstable During Heating

General faulty parts:

1. Fuel with water; 2. Coolant temperature sensor; 3. Spark plug; 4. Throttle body and idle speed

bypass air duct; 5. Air intake duct; 6. Idle speed stepper motor; 7. Engine mechanical part. General diagnostic flow:

77

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check the air filter for blockage and the air intake duct for air leakage.

Yes

Service the air intake system

No

Next step

2

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

3

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

4

Unplug the connector of coolant temperature sensor, start the engine and observe if unstable idling occurs when the engine is heated.

Yes

Service the line or replace the sensor

No

Next step

5

Remove the fuel injector and check it for leakage, blockage or poor flow with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

6

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

7

Check the pressure of all engine cylinders and observe if it varies greatly.

Yes

Troubleshoot the engine mechanical malfunction

No

Next step

8

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

Section 8 Engine Normally Started, yet Idling Unstable after Heating

General faulty parts:

1. Fuel with water; 2. Coolant temperature sensor; 3. Spark plug; 4. Throttle body and idle speed

bypass air duct; 5. Air intake duct; 6. Idle speed stepper motor; 7. Engine mechanical part. General diagnostic flow:

78

No.

Operating Steps

Test Result

Follow-up

Steps

1

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

2

Observe if the engine output power increases when the A/C system is started, that is, to observe the change in ignition advance angle, fuel injection pulse width and air intake flow with the diagnostic tester for EFI system.

Yes

To Step 4

No

Next step

3

Connect the adapter of EFI system, disconnect the cable of 75# pin of ECU and check if there is high level signal at the end of wire harness when the A/C system is turned on.

Yes

Next step

No

Service the A/C system

4

Check if the A/C system pressure, the compressor electromagnetic clutch and the A/C compressor pump are normal.

Yes

Next step

No

Service the A/C system

5

Remove the fuel injector and check it for leakage, blockage or poor flow with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

6

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check if the throttle cable is stuck or too tight.

Yes

Adjust

No

Next step

2

Check the air intake system and the connected vacuum line for leakage.

Yes

Service the air intake system

No

Next step

Section 9 Engine Normally Started, yet Idling Unstable or Stalling Under Partial Load (e.g. A/C Turned on)

General faulty parts:

1. A/C system; 2. Idle speed stepper motor; 3. Fuel injector.

General diagnostic flow:

Section 10 Engine Normally Started, yet Idling at a Higher Speed

General faulty parts:

1. Throttle body and idle speed bypass air duct; 2. Vacuum tube; 3. Idle speed stepper motor; 4.

Coolant temperature sensor; 5. Ignition timing; General diagnostic flow:

79

3

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

4

Unplug the connector of coolant temperature sensor, start the engine and observe if it idles at a higher speed.

Yes

Service the line or replace the sensor

No

Next step

5

Check if the ignition timing of the engine meets the specifications.

Yes

Next step

No

Service the ignition timing

6

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check the air filter for blockage.

Yes

Service the air intake system

No

Next step

2

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

3

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

4

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

5

Check if the intake air pressure sensor and the throttle position sensor as well as their lines are normal;

Yes

Next step

No

Service the line or replace the sensor

Section 11 Engine Running Slowly or Stalling During Acceleration

General faulty parts:

1. Fuel with water; 2. Intake air pressure sensor and throttle position sensor; 3. Spark plug; 4.

Throttle body and idle speed bypass air duct; 5. Air intake duct; 6. Idle speed stepper motor; 7. Fuel injector; 8. Ignition timing; 9. Bleeding pipe. General diagnostic flow:

80

6

Remove the fuel injector and check it for leakage or blockage with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

7

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

8

Check if the ignition order and ignition timing of the engine meet the specifications.

Yes

Next step

No

Service the ignition timing

9

Check the bleeding pipe for smooth bleeding.

Yes

Next step

No

Repair or replace the bleeding pipe

10

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check the air filter for blockage.

Yes

Service the air intake system

No

Next step

2

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

3

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

4

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

5

Check if the intake air pressure sensor and the

Yes

Next step

Section 12 Slow Response in Acceleration

General faulty parts:

1. Fuel with water; 2. Intake air pressure sensor and throttle position sensor; 3. Spark plug; 4.

Throttle body and idle speed bypass air duct; 5. Air intake duct; 6. Idle speed stepper motor; 7. Fuel injector; 8. Ignition timing; 9. Bleeding pipe. General diagnostic flow:

81

throttle position sensor as well as their lines are normal;

No

Service the line or replace the sensor

6

Remove the fuel injector and check it for leakage or blockage with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

7

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

8

Check if the ignition order and ignition timing of the engine meet the specifications.

Yes

Next step

No

Service the ignition timing

9

Check the bleeding pipe for smooth bleeding.

Yes

Next step

No

Repair or replace the bleeding pipe

10

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

No.

Operating Steps

Test Result

Follow-up

Steps

1

Check for slipping clutch, low tire pressure, braking drag, incorrect tire size, improper four wheel alignment, etc.

Yes

Repair

No

Next step

2

Check the air filter for blockage.

Yes

Service the air intake system

No

Next step

3

Connect the fuel pressure gauge (front end of fuel rail assembly oil inlet as connecting point), start the engine and check if the fuel pressure is about 350kPa.

Yes

Next step

No

Service the oil supply system

4

Pull out the ignition coil from one cylinder, connect a spark plug and keep its electrodes about 5mm

Yes

Next step

Section 13 Sluggish Acceleration and Poor Performance

General faulty parts:

1. Fuel with water; 2. Intake air pressure sensor and throttle position sensor; 3. Spark plug; 4.

Ignition coil; 5. Throttle body and idle speed bypass air duct; 6. Air intake duct; 7. Idle speed stepper motor; 8. Fuel injector; 9. Ignition timing; 10. Bleeding pipe. General diagnostic flow:

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away from the engine body, start the engine and check for normal high-pressure fire.

No

Service the ignition system

5

Check the spark plug for each cylinder and observe if its model and clearance meet the specifications.

Yes

Next step

No

Adjust or replace

6

Remove the idle speed stepper motor and check the throttle body, the idle speed stepper motor and the idle speed bypass air duct for carbon deposition.

Yes

Clean relevant parts

No

Next step

7

Check if the intake air pressure sensor and the throttle position sensor as well as their lines are normal;

Yes

Next step

No

Service the line or replace the sensor

8

Remove the fuel injector and check it for leakage or blockage with a dedicated cleaning analyzer.

Yes

Replace the faulty part

No

Next step

9

Check the fuel and observe if the malfunction is caused just after fueling up.

Yes

Replace the fuel

No

Next step

10

Check if the ignition order and ignition timing of the engine meet the specifications.

Yes

Next step

No

Service the ignition timing

11

Check the bleeding pipe for smooth bleeding.

Yes

Next step

No

Repair or replace the bleeding pipe

12

Connect the adapter of EFI system, turn on the ignition switch and check if the power supply for 12#, 13#, 44#, 45# and 63# pin is normal; check if the 3#, 51#, 53#, 61# and 80# pin are normally grounded.

Yes

Diagnosis help

No

Service the relevant line

Part 6 Guide for Use of BYD-ED300 Electric Diagnostic Tester

As the latest generation of electric diagnostic tester, BYD-ED300 is intended for all autos developed by BYD AUTO, which not only features easy online upgrade for troubleshooting the future models developed by BYD AUTO, but also has extended functions like certain waveform display and can be used as a simple oscilloscope.

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Section 1 Preparation for Troubleshooting with BYD-ED300

1.1 Preparation and Connection for Troubleshooting

1.1.1 Preparation with BYD-ED300

1.1.1.1 General Test Condition

1) Turn on the power switch of a car;

2) The battery voltage shall be 11~14V and the rated voltage of BYD-ED300 is 12V.

1.1.1.2 Connect BYD-ED300

BYD-ED300 is connected in the following steps:

♦ Insert the diagnostic card into the BYD-ED300 card slot properly and keep the side with words ―UP SIDE‖ facing upwards. ♦ Insert the DB15 end of BYD-ED300 diagnostic cable into the data interface ―DATA I/O‖ on the

tester. ♦ Connect the other end OBDII to the vehicle diagnostic socket.

Instructions: In case of insufficient power supply for vehicle diagnostic socket or damaged power supply pins, power supply can be obtained in the following ways: ♦ By cigar lighter cable: take out the cigar lighter, insert one end of its cable to the cigar lighter hole on the car and connect the other end to the power plug of BYD-ED300 main test cable. Shut down BYD-ED300 before turning off the ignition switch so as to avoid illegal shutdown. ♦ By twin-caliper power cord: clamp the positive and negative terminal of battery with the two power cord calipers and insert the other end to the power plug of BYD-ED300 main test cable.

♦ By extension cable: insert the DB25 end of extension cable to the “Extension Interface”

on the tester, connect the DV terminal of extension cable to the dedicated power adapter jack, and then insert the other end of power adapter to the 100-240V AC power socket.

1.2 Start Vehicle Diagnosis

You can start diagnosis with the electric diagnostic tester after all preparations are completed.

Section 2 Instructions for Keypad Operation

2.1 Keyboard Layout

BYD-ED300 electric diagnostic tester is operated with dome as per the simple operation prompts

shown on the display; users can also read ―Operating Guide for Electric Diagnostic Tester‖ for the

basic operations. The following contents in this guide will be not described again.

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Dome layout is shown below:

2.2 Key Functions

Number key 0-9: menu selection; digital input.

Direction key ↑↓←→: ↑ and ↓ for menu selection; ← and → for page flipping; in case of digital

input, press ↑ to add 1, ↓ to deduct 1 and ← to backspace and clear the previous digit; in case of

action test for components, press ← to shut down and → to enable or start.

Reset key RST: system reset. Notice: Use it with caution. Press and hold this key for 1~2 seconds and then release it. Return/Exit key ESC: return to parent directory; exit the current function page; exit current setting.

Confirmation key OK: enter subdirectory; confirm to perform a certain function. Multifunction key F1 and F2: F1 is used to display help; F2 is used to print the current page;

these two keys can be used as auxiliary input keys in special conditions, like -/+. Refer to the relevant prompts.

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Section 3 Functions

3.1 Display Interface

The display interface of electric diagnostic tester is divided into three areas: title bar, information bar and help bar, as shown in the figure below:

and takes about 1~2 minutes, as shown in the figure on the right.

Title bar – to display title information Information bar: to display main content. Display various menu, diagnosis information, etc. Help bar – to display current operation prompts as well as other auxiliary information.

3.2 Software Upgrade

First insert the dedicated diagnostic card into

the ―Card Slot‖ on the tester (keep the side

with words ―UP SIDE‖ facing upward and the

card resists improper insertion) and then turn on the power supply. Then, the tester will automatically detect the validity of the diagnostic card. If valid, it continues to detect whether the software in the tester has the same version as that in the diagnostic card; if different, the tester copies the software in the card to the ROM of tester and run it. This process is called smart software upgrade for the tester

Warning: Do not power off, reset the system with [RST] or pull out the diagnostic card during upgrading the software; otherwise, it may cause an upgrading failure, even system crash. If the diagnostic tester cannot be used for this reason, please return it to BYD After-Sales Service.

Instructions: Smart software upgrade for the tester only occurs when the version of software in the tester is inconsistent with that in the diagnostic card.

3.3 Basic Functions of Diagnostic Tester Electric diagnostic tester ED300 has two functions: software upgrade for diagnostic card and diagnosis for specific model. Additional functions are still available, like diagnostic tester setting. Examples are shown below: Please refer to relevant instructions for software upgrade if necessary.

3.3.1 Diagnosis for a specific model This manual only shows the operations for EMS DELPHI-MT20U2 of F3 auto. Please refer to it for other systems.

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Please select ―EMS‖, as shown in the figure

on the right.

Operating skills: in most menu selection pages, users can press the number shown in front of the menu item to enter relevant menu. For example: to diagnose F3 auto, first press

↑ (↓) to select the F3 and press OK; or just

press [1].

Select ―F3‖ in the model selection interface, as

shown in the figure on the right.

Please select ―DELPHI-MT20U2‖, as shown in the figure on the right.

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If BYD-ED300 diagnostic tester is successfully communicated with ECU, it will be shown in the figure on the right.

―Title Bar‖ displays the name of currently

diagnosed system: ECU-MT20U2.

Instructions: two ways are still available for users to diagnose certain function: first,

press ↑ and ↓ to change the menu item

indicated by [→] and then press [OK]; second, directly press the number in front of menu item. Operations will not be described again. For operation, please refer to the prompts on the display.

3.3.1.1 Read computer version

The computer version information is a group of numbers defined by the manufacturer to identify some basic information, like Vehicle Identification Number, displayed on the BYD-ED300 as shown in the figure on the right.

Instruction: this information is from ECU, which varies with different ECU. Please feed back to the relevant department of BYD AUTO during maintenance.

3.3.1.2 Read DTC Malfunction detected by ECU can be displayed in the form of specific code (DTC).

 If no trouble with system

You will be prompted with ―No Trouble with

System‖ by BYD-ED300, as shown in the

figure.

 If trouble with system

All the DTCs and relevant trouble information

will be listed in the ―Information Bar‖, as

shown in the figure on the right.

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3.3.1.3 Clear DTC It is intended to clear some historical or intermittent malfunctions recorded in ECU. If DTC is successfully cleared, ―DTC Cleared‖ will be displayed as shown in the figure on the right. You are recommended to repeat the action twice or three times to ensure DTC is cleared completely.

"Page:1/2‖ at the upper right corner of screen means the received malfunction information is shown on two pages and the current page is the first one; to view other information, users

can press [→] to turn to page 2, following the prompts shown in the ―Help Bar‖. Also, users

can press [←] to turn to page 1.

3.3.1.4 Read data stream BYD-ED300 diagnostic tester supports two display modes: common display and graphic display. Graphic display is much convenient and visualized, which helps ED300 make greater progress than the diagnostic testers designed by BYD AUTO in the past. For the switch between the two modes, please refer to the prompts of the ―Help bar‖ of BYD-ED300.

 Common display mode

The content displayed in the ―Information Bar‖

is displayed as shown in the figure. The first page is displayed now. To view other data content, users can turn to a specific page by pressing ← and →.

 Graphic display mode

In graphic display mode, BYD-ED300 can display the graph of two parameters on each page. The maximum value, intermediate valve and minimum value of a parameter is respectively displayed on the left of each graph. Also, relevant texts will be displayed below the graph.

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Data stream

Voltage of oxygen sensor 2

Graphic display realizes the dynamic change by drawing dots regularly from left to right.

Page indicator ―Page: 4/4‖ will also be

displayed on the upper right corner of ―Information Bar‖. Please refer to the operations above to turn the page. Graphic display includes two modes.

Second is to adopt bar graph, as shown in the figure on the right.

These two ways are interchangeable. Please refer to relevant prompts in ―Help Bar‖. Like common display mode, the current graph in graphic display mode can also be printed

out by a miniprinter. Refer to prompts in ―Help

Bar‖ for the operations.

First is to draw dots, as shown in the figure on the right.

3.3.1.5 Component action test The component action test for MT20U2 system is divided into three different control modes, switching variable, control variable and activation variable, as shown in the figure on the right.

The action for each variable is carried out in different ways, which will be described below.

 Switching variable

It means only two states for these variables: ON or OFF, so users just need to perform simple operations to complete relevant action.

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―★‖ indicates the variable currently controlled.

Meanwhile, the current operation status expected by users will also be displayed on the right: ON or OFF. To select an item to be

tested, users can press ↑ and ↓. Press ← and → to control the current switching value, ← to

turn it on and → to turn it off.

To give up the right of control of currently

selected item, just press ↑ and ↓ to select

other items to be tested or press [ESC] to exit the current page.

 Control variable

It refers to some setting variables. By setting these variables, the internal variables of ECU can be changed so as to change the working conditions of engine.

―★‖ indicates the item can be set now. To select a variable to be set, users can press ↑

and ↓.

The setting range for current item is displayed

on the second line in the ―Help Bar‖ and the

value input by user is displayed on the third line. The fourth line provides the prompts for users that they can press [OK] to set the current item. After entering a value, users can press [OK] to set; then, the result will be displayed on the fourth line.

To give up the right of control of currently

selected item, just press ↑ and ↓ to select

other items to be tested or press [ESC] to exit the current page.

 Activation variable

It is controlled in the way similar to switching variable. It is displayed as shown in the figure on the right. For operations, please refer to that of ―Switching Variable‖ mentioned above.

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Instructions: use “Component Action Test”

with caution. Non-professional technicians or professional service man are not allowed to use this function, as improper operation may damage the engine system.

3.3.1.6 System reset

System reset causes ECU to take a self-reset action. If the system is reset successfully,

―Reset Complete‖ will be shown on

BYD-ED300.

3.3.2 Diagnostic card burning

Please connect the DB25 end of the dedicated extension cable to the ―Extension

Interface‖ on the tester and the DB9 end to

the computer serial port, then connect the input end of power adapter to the power input end of the extension cable and at last connect the power adapter to the household utility power (220V AC power). In this way, the diagnostic tester can work normally. The connection diagram is shown in the figure below.

During burning the diagnostic card, there are two conditions as per the settings at the end of PC.

1. If ―Program File‖ is selected in burning

software, update the diagnostic program in the diagnostic card.

2. If ―Font File‖ is selected in burning software,

update the font program in the diagnostic card. This function is not usually used, as the font library of required simplified Chinese characters has been stored in the diagnostic

card by the manufacturer.

Instructions: the diagnostic program and font program are stored in two different areas of the diagnostic card. Thus, users must be sure which one is required to be updated.

Press OK in the interface mentioned above

and you will be prompted ―Ready. Please run DTcard_Updata.exe...‖, as shown in the figure

on the right. Then, please run DTcard_Updata.exe on the computer. To upgrade the diagnostic card, configure this software properly and select the program file to be burned. Please refer to Using Help for DTcard_Updata.exe.

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Warning: Please ensure burning is completed naturally! Do not power off the tester, reset it with [RST] or pull out the diagnostic card; otherwise, it may cause an upgrading failure and even damage the

diagnostic card. “Naturally Complete”

refers to that burning is completed with dedicated burning software

DTcard_Updata.exe and “Burning

Complete” is shown on the display.

3.3.3 Version Information of Diagnostic Tester

Select ―Version Information of Diagnostic Tester‖ in the main interface. Such information

as software version, hardware version and date of manufacture will be displayed, as shown in the figure on the right.

Users can know the version information clearly and can visit the official website of BYD AUTO to ensure whether the software needs to be upgraded.

3.3.5 Operating Guide for Diagnostic Tester

Select ―Operating Guide for Diagnostic Tester‖

in the main interface, as shown in the figure on the right. General operations will be displayed here while specific operations may

also be simply displayed in ―Help Bar‖ on each

page.

Instructions: the displayed content is only for your reference, which may also be displayed when you turn on the diagnostic tester.

3.3.4 Diagnostic Tester Settings

Select ―Diagnostic Tester Settings‖ in the main

interface. The working conditions of diagnostic tester ED300 can be set here: backlight switch, display font, data refresh speed, etc.

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No.

Part name

Mounting torque

(NM)

1

Intake air

pressure/temperature

sensor

3.3

2

Coolant temperature

sensor

20 (Max)

3

Knock sensor

20±5

4

Oxygen sensor

50±10

5

Throttle position sensor

2±0.5

6

Crankshaft position

sensor

8±2

7

Camshaft position

sensor

8±0.5

8

Fuel injector

6

9

Idle speed stepper motor

(First stage) 2±1

(Second stage) 7±1

Item

Mileage

x1000km

10

20

30

40

50

60

70

80

Months

3 6 9

12

15

18

21

24

Ignition coil

I I I I

Spark plug

I I I R

Ignition timing

I I I I

Engine idling

I I I I

Fuel tank

I C

Fuel filter

R R R R

Fuel injector

C* C* C* C*

Air filter

I R I R

Stepper motor air duct

C C C C

Throttle body

C C C C

Emission inspection

I I I I

Diagnostic tester check

I I I I

Part 7 Accessories

Section 1 Table of Mounting Torque for Parts

Section 2 Rules for Maintenance of EFI System

2.1 Family cars

Instructions:

1. The rules for maintenance are applicable for family cars;

2. Interval of vehicle maintenance depends on the reading on the odometer or the time interval,

whichever comes earlier.

3. The rules for maintenance must be strictly complied with, which are developed based on

normal use of vehicle as per design.

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Item

Mileage

x1000km

20

40

60

80

100

120

140

160

Months

3 6 9

12

15

18

21

24

Ignition coil

I I I I I I I

I

Spark plug

I R I

R

Ignition timing

I I I

I

Engine idling

I I I

I

Fuel tank

C

Fuel filter

R R R R R R R

R

Fuel injector

C*

Air filter

I R I R I R I

R

Stepper motor air duct

I C I C I C I

C

Throttle body

I C I C I C I

C

Emission inspection

I I I

I

Diagnostic tester check

I I I

I

Description

DTC

byd F3 (2015) Workshop manual

Specifications and Main Features

Frequently Asked Questions

User Manual