Yanmar 3TNV82A, 4TNV1006T Troubleshooting Manual

TROUBLESHOOTING

Gehl Form No. 50950006, AP1210

MANUAL

ELECTRONIC CONTROL

3TNV82A

3TNV82A-B

3TNV84

3TNV84T

3TNV84T-B

3TNV88

3TNV88-B

3TNV88-U

4TNV84

4TNV84T

4TNV84T-Z

4TNV88

4TNV88-B

4TNV88-U

4TNV94L

4TNV98

4TNV98-Z

4TNV98-E

4TNV98T

4TNV98T-Z

4TNV106

4TNV106T

California

Proposition 65 Warning

California

Proposition 65 Warning

Diesel engine exhaust and some of its
constituents are known to the state of
California to cause cancer, birth
defects, and other reproductive harm.

Battery posts, terminals, and related
accessories contain lead and lead
compounds, chemicals known to the
state of California to cause cancer and
reproductive harm.

Wash hands after handling.

TNV DI Service Manual

Section 1

FAILURE DIAGNOSIS

Page

DTCs (Diagnostic Trouble Codes) General Description.................. 1-3

DTC Code List........................................................................... 1-3

Description Items....................................................................... 1-7

Analog Input Related Failures................................................... 1-8

Pulse Sensor Related Failures................................................ 1-60

Contact Output Related Failures............................................. 1-66

Contact Input Related Failures.............................................. 1-100

Actuators etc.......................................................................... 1-114

E-ECU Internal and Communication Errors........................... 1-122

Method and Procedure of Failure Diagnosis............................... 1-133

Description Items................................................................... 1-133

Analog Input Related Failures............................................... 1-136

Pulse Sensor Related Failures.............................................. 1-164

Contact Output Related Failures........................................... 1-170

Contact Input Related Failures.............................................. 1-187

Actuator Related Failures...................................................... 1-193

ECU Internal and Communication Errors.............................. 1-197

FAILURE INDICATOR LAMP FLASHING PATTERN........... 1-207

Using the Failure Indicator for Failure Diagnosis ........................ 1-208

Flashing Patterns of the Failure Indicator.............................. 1-208

Factor Analysis............................................................................ 1-210

2G-Type Eco-Governor Speed-Fluctuation Factor Analysis. 1-210
2G-Type Eco-Governor Engine

Stalling/Start-Up Inability Factor Analysis.............................. 1-213

2G-Type Eco-Governor Black Smoke Factor Analysis.......... 1-216

Special Service Tools.................................................................. 1-218

Troubleshooting By Measuring Compression Pressure.............. 1-219

Compression Pressure Measurement Method...................... 1-219

Quick Reference Table For Troubleshooting .............................. 1-222

TNV DI Service Manual

1-1

FAILURE DIAGNOSIS

This Page Intentionally Left Blank

1-2

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

DTCS (DIAGNOSTIC TROUBLE CODES) GENERAL DESCRIPTION

DTC Code List

Clas

sifica

tion

Analog Input Related Failures

DTC

P1202/4
P1203/3 Error (high voltage) P.1-10
P0122/4

P0124/2 Intermittent failure P.1-16
P1125/1 Error (foot pedal-close position) P.1-18
P1126/0 Error (foot pedal-open position) P.1-20
P0222/4

P0224/2 Intermittent failure P.1-26
P1225/1 Error (foot pedal-close position) P.1-28
P1226/0 Error (foot pedal-open position) P.1-30
P1227/8 Error (pulse communication) P.1-32 P.1-152
P0222/4

P0224/2 Intermittent failure P.1-38
P0668/4

P1644/2 Intermittent failure P.1-42
P0634/0 2-5
P0117/4

P0119/2 Intermittent failure P.1-49
P0217/0 3-6
P0642/4

P1644/2 Intermittent failure P.1-55
P0562/1
P0563/0 Error (High Voltage) P.1-58 P.1-58

Lamp

Flashing
Patterns

Area Status Overview

7 Rack position sensor

5 Accelerator sensor

1-8 Spare accelerator sensor

1-9

4-1

4

2-4 SENSOR 5V

2-3 Power supply Voltage

Atmospheric pressure
sensor

ECU Temperature
Sensor

ECU Temperature Rise
Alarm

Cooling water
temperature sensor

Cooling Water
Temperature Rise Alarm

Error Item

Error (low voltage) P.1-8

Error (low voltage) P.1-12

Error (low voltage) P.1-22

Error (low voltage) P.1-34

Error (low voltage) P.1-40

Error (Low Voltage) P.1-45

Error (low voltage) P.1-53

Error (Low Voltage) P.1-56 P.1-56

Referenced page

number

Diagnosis

P.1-43 P.1-154

P.1-51 P.1-156

Failure

P.1-136

P.1-140P1203/3 Error (high voltage) P.1-14

P.1-144

P.1-148P0223/3 Error (high voltage) P.1-24

P.1-144

P.1-148P0223/3 Error (high voltage) P.1-36

P.1-154P0669/3 Error (high voltage) P.1-41

P.1-156P0118/3 Error (High Voltage) P.1-47

P.1-160P0643/3 Error (High Voltage) P.1-54

TNV DI Service Manual

1-3

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Clas

sifica

tion

Pulse Sensors

Contact Output Related Failures

Lamp

DTC

P0340/4 6 Speed Sensor Error P.1-60 P.1-164
P1340/4 1-1 Spare speed sensor Error P.1-62 P.1-167

P0219/0 9 Overspeed Error P.1-64 P.1-64

P1222/4

P1224/2 Intermittent failure P.1-70
P1232/4

P1234/2 Intermittent failure P.1-76
P1242/4

P1244/2 Intermittent failure P.1-82
P1402/4
P1403/3 Error B (Step Motor A-Phase) P.1-86
P1412/4 Error A (Step Motor B-Phase) P.1-88
P1413/3 Error B (Step Motor B-Phase) P.1-90
P1422/4 Error A (Step Motor C-Phase) P.1-92
P1423/3 Error B (Step Motor C-Phase) P.1-94
P1432/4 Error A (Step Motor D-Phase) P.1-96
P1433/3 Error B (Step Motor D-Phase) P.1-98
P1192/4 2-1 Oil pressure switch Error P.1-100
P1198/1 3-1 Oil Pressure Descend Error P.1-102
P1562/4 2-2 Charge switch Error P.1-104
P1568/1 3-2 Charge Alarm P.1-106
P1217/0 3-3 Abnormal Water Temperature P.1-108
P1101/0 3-4 Air cleaner Clogging Alarm P.1-110

Flashing
Patterns

1-7 Rack actuator Relay

1-5 Start Assist Relay

1-4 CSD solenoid valve

1-3 EGR valve

Area Status Overview

Error Item

Error A P.1-66

Error A P.1-72

Error A P.1-78

Error A (Step Motor A-Phase) P.1-84

Referenced page

number

Failure

Diagnosis

P.1-170P1223/3 Error B P.1-68

P.1-174P1233/3 Error B P.1-74

P.1-178P1243/3 Error B P.1-80

P.1-182

P.1-187

Contact Input Related Failures

1-4

P1151/0 3-5 Oil-water separator Alarm P.1-112

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

Clas

sifica

tion

DTC

P1212/4
P1213/3 Error (high current) P.1-116
P1211/7 Mechanical failure P.1-118

P1214/2 Engine Error P.1-120

Actuator Errors

P0605/12

P1605/2 Error (Checksum B)
P1606/2 Error (Checksum C)

P1620/12 Map format Error

P1601/2
P0601/12 Error (read/write error)
P1610/12
P1611/12 Error B
P1612/12 Error C

P0686/4 1-6 Main relay Error P.1-124 P.1-199
U0001/12 1-2 CAN Communication Error P.1-126 P.1-203
U0167/12

U1167/8 Error (pulse communication) P.1-130

U0426/2 Error (System) P.1-132

ECU inside and Communication Related Failures

Lamp
Flashing
Patterns

Rack actuator

8

4-1

4-2 Immobilizer

ECU
Internal

Error Item

Area Status Overview

Error (low current) P.1-114

Error (Checksum A)

Flash ROM

EEPROM

Sub CPU

Error (Checksum)

Error A

Error (CAN communication) P.1-128

Referenced page

number

P.1-122

P.1-123

Failure

Diagnosis

P.1-193

P.1-197

P.1-205

TNV DI Service Manual

1-5

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

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1-6

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Description Items

DTC Code Number DTC Name

DTC Detecting Conditions

FAILURE DIAGNOSIS

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Precondition for Error detection

2. Error detecting Condition

3. Indicates the pattern in which the failure lamp flashes when the
DTC is output. (For detailed information on various flashing
patterns, see Annex).

This column shows what parts or
items should be checked to identify
the cause of the error.
For details, see "<Diagnosis
Description>."

Check points

Movement at Error occurrence

Error Mode [Operation Continuation] / [Run Under Restrictions] / [Stop Immediately]:

The engine operation after detecting the error is described.
*

[Operation Continuation]:After detecting the error, the system lets the engine

continue to run without any restrictions.

[Run Under Restrictions]:The system lets the engine continue to run but restricts the

High idle speed, engine power, and/or other performance
factors as appropriate.

[Stop Immediately]: The system stops the engine immediately after detecting the

error.When any error is detected before starting the engine, the
starter will not rotate.

Run restricted? Yes/No.: If Yes, this field details how the engine run is restricted when the error has

occurred.

Recovery
Conditions

Yes/No.: If Yes, this field describes what conditions must be true for the error mode

to be reset.

Remarks This field describes some notes on safety precautions and so on, as appropriate.

Estimation of Failure cause/Error condition

Provides descriptive information on possible points of failure, possible direct causes (such as a disconnected sensor
wire), or possible system abnormalities that has indirectly caused the failure (such as abnormally high cooling water
temperature), as can be estimated from the output DTC.

Note: Indicates failures that might be related with the output DTC.

Diagnosis Description

Describes methods or procedures of failure d iagnosis.

* After sucessful recovery by the replaceme nt of ECU, sensor or actuato r , make sure that installing

the previous parts will reproduce the same error.

TNV DI Service Manual

1-7

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Analog Input Related Failures

Rack position sensor

(1) P1202/4: Failure with Rack Position Sensor (Low Voltage)

DTC P1202/4 Rack Position Sensor Error (Low Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. The sensor voltage lower limit and below [at E-ECU activation,
engine running]

3. Seven flashes.

Connector
Harness
Rack position sensor
E-ECU

Check points

Movement at Error occurrence

Error Mode [Run Under Restrictions]:

The engine continues to run in on-error engine control mode.
If any error is detected at E-ECU activation, it takes 1 - 10 seconds from the starter
begins to rotate until the engine starts.

Run restricted? Yes: • The High idle speed is restricted to one of the following, whichever smaller:

• 80% of the pre-error High idle speed

• 150% of the Low idle speed

• The fuel injection rate is restricted.

Recovery

No.

Conditions
Remarks The High and Low idle speeds must be equal to those specified in the engine

specifications.

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The rack position sensor's signal wires ma y be disconnected or short-circuited with GND .

• The SENSOR 12V wire may be disconnected or short-circuited with GND (*NOTE).

• The SENSOR GND wire may be short-circuited with POWER SUPPLY (*NOTE).

*NOTE) If the SENSOR 12V wire is short-circuited wi th GND or SE NSOR GND wire is shor t-circuited with

POWER SUPPLY, the E-ECU's po wer supply line fuse 10A might be blo wn.With this fuse b lown, the
E-ECU may fail to detect/ind icate the error, and to store the error history .

The rack position sensor may be faulty.

• Output defect of the r ack position signal by a disconnection or a short circuit of the inner wiring

• The E-ECU internal circuitry may be faulty.

1-8

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage (AD value).
*For details of the method and the procedure of diagnosis, see P.1-136

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the rack actuator is correctly inserted.

• Check that the wiring of the rack actuator is not disconnected or the insulation
of the wiring is not peeled.

• Check the input voltage of the rack position sensor (voltage of the sensor 12V
line).

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-136

TNV DI Service Manual

1-9

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P1203/3: Failure with Rack Position Sensor (High Voltage)

DTC P1202/3 Failure with Rack Position Sensor (High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. The sensor voltage upper limit and above [at E-ECU activation,
engine running]

3. Seven flashes.

Movement at Error occurrence

Detection at the engine start Detection at the engine running

Error Mode [Run Under Restrictions]:

Start the engine in on-error engine control
mode.
It takes 1 to 10 seconds from the starter’s
rotation to the engine start.

Run restricted? Yes: • The High idle is restricted to one of

the following, whichever smaller:

• 80% of the pre-error High idle speed

• 150% of the Low idle speed

• The fuel injection rate is restricted.

Recovery

No. No.

Conditions
Remarks The High and Low idle speeds must be

equal to those specified in the engine
specifications.

Check points

Connector
Harness rack position sensor
Rack actuator
E-ECU

[Stop Immediately]:
The engine stops running.

Yes: The rack actuator relay is turned

OFF, and the rack position is forcibly
set to the engine stop position.

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The SENSOR GND wire may be disconnected.

• The rack position sensor signal wire ma y be short-circuited with POWER SUPPLY .

• The rack actuator wiring ma y be short-circuited with GND (with engine running).

• The rack position sensor may be faulty.

• Output defect of the r ack position signal by a disconnection or a short circuit of the inner wiring

• The rack actuator may be faulty.

• The rack actuator inner wiring ma y be short-circuited with GND (with engine running).

• The E-ECU internal circuitry may be faulty.

1-10

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage (AD value).
*For details of the method and the procedure of diagnosis, see P.1-136

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the rack actuator is correctly inserted.

• Check that the wiring of the rack actuator is not disconnected or the insulation
of the wiring is not peeled.

• Check the input voltage of the rack position sensor (voltage of the sensor 12V
line).

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-136

TNV DI Service Manual

1-11

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Accelerator sensor

(1) P0122/4: Accelerator Sensor Error (Low Voltage)

DTC P0122/4 Accelerator Sensor Error (Low Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 0.2 [V] or lower.

3. Five flashes.

Movement at Error occurrence

Spare Accelerator Sensor Function

Unavailable Available

Error Mode [Run Under Restrictions]:

The engine runs at a constant rotational
speed.

Run restricted? Yes: The target speed is set to the "on-

error target speed (standard value:
1500[min

-1

])" or “pre-error target

speed”.

Recovery
Conditions

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Remarks

Check points

Harness
Accelerator sensor

[Stop Immediately]:
The engine continues to run using the
spare accelerator sensor instead.

No.

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The accelerator sensor's signal wires ma y be disconnected or short-circuited with GND .

• The SENSOR 5V wire may be disconnected o r short-circuited with GND.

• The SENSOR GND wire may be short-circuited with POWER SUPPLY (*NOTE).

*NOTE) If the SENSOR GND wire is short-circuited with PO WER SUPPL Y , the E-ECU's po wer supply line fuse

10A might be blown.With this fuse blown, the E-ECU may fail to detect/indicate the error , and to store
the error history.

• The accelerator sensor may be faulty.

• Sensor output defect by a disconnection of the accelerator sensor inner wiring or a sliding resistance

increase

• The E-ECU internal circuitry may be faulty.

1-12

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-140

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the accelerator sensor is correctly inserted.

• Check that the wiring of the accelerator sensor is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the accelerator sensor.

• Check the harness for correct continuity.

• Check the output voltage of the accelerator sensor.

*For details of the method and the procedure of diagnosis, see P.1-140

TNV DI Service Manual

1-13

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P0123/3: Accelerator Sensor Error (High Voltage)

DTC P0123/3 Accelerator Sensor Error (High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 4.6 [V] or higher.

3. Five flashes.

Movement at Error occurrence

Spare Accelerator Sensor Function

Unavailable Available

Error Mode [Run Under Restrictions]:

The engine runs at a constant rotational
speed.

Run restricted? Yes: The target speed is set to the "on-

error target speed (standard value:

-1

1500[min

])" or “pre-error target

speed”.

Recovery
Conditions

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Remarks

Check points

Harness
Accelerator sensor

[Stop Immediately]:
The engine continues to run using the
spare accelerator sensor instead.

No.

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The SENSOR GND wire may be disconnected.

• The sensor signal wire may be short-circuited with POWER SUPPLY.

• The accelerator sensor may be faulty.

• Sensor output defect by a short circuit with pow er supply of the accelerator sensor inner wiring

• The E-ECU internal circuitry may be faulty.

1-14

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic

Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-140

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the accelerator sensor is correctly inserted.

• Check that the wiring of the accelerator sensor is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the accelerator sensor.

• Check the harness for correct continuity.

• Check the output voltage of the accelerator sensor.

*For details of the method and the procedure of diagnosis, see P.1-140

TNV DI Service Manual

1-15

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P0124/2: Intermittent Failure with Accelerator Sensor

DTC P0124/2 Intermittent Failure with Accelerator Sensor

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Connector
Harness
Accelerator sensor

Check points

Movement at Error occurrence

Error Mode [Run Under Restrictions]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• Accelerator sensor signal wire ma y be disconnected, or short-circuited with GND or power supply.

• Sensor 5V wire may be disconnected, or short-circuited with GND or power supply.

• Sensor GND wire may be disconnected.

• The accelerator sensor may be faulty.

• Inner wiring may be disconnected or short-circuited

1-16

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-140

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the accelerator sensor is correctly inserted.

• Check that the wiring of the accelerator sensor is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the accelerator sensor.

• Check the harness for correct continuity.

• Check the output voltage of the accelerator sensor.

*For details of the method and the procedure of diagnosis, see P.1-140

TNV DI Service Manual

1-17

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(4) P0123/1: Accelerator Sensor Error (foot pedal-close position)

DTC P1125/1 Accelerator Sensor Error (foot pedal-close position)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. With sensor voltage at or below 0.65[V], foot pedal Normally

Harness
Foot pedal

Check points

Open switch detected being ON or foot pedal Normally Closed
Switch detected being OFF.

3. Five flashes.

Movement at Error occurrence

Error Mode [Run Under Restrictions]:

The engine runs at a constant rotational speed.

Run restricted? Yes: The target speed is set to the "on-error target speed (standard value: 1500[min-1])"

or “pre-error target speed”.

Recovery

No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The wiring for the f oot pedal Normally Closed switch ma y be disconnected.

• The wiring for the f oot pedal Normally Open switch ma y be short-circuited with GND .

• The foot pedal may be faulty.

• The foot pedal inner wiring ma y be disconnected or short-circuited with GND .

• The E-ECU internal circuitry may be faulty.

1-18

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check that the foot pedal movement is correctly recognized.
*For details of the method and the procedure of diagnosis, see P.1-144

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the foot pedal is correctly inserted.

• Check that the wiring of the foot pedal is not disconnected or the insulation of
the wiring is not peeled.

• Check the foot pedal for correct continuity.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-144

TNV DI Service Manual

1-19

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(5) P1126/0: Accelerator Sensor Error (foot pedal-open position)

DTC P1126/0 Accelerator Sensor Error (foot pedal-open position)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. With sensor voltage 1.1[V] and above, foot pedal Normally Open

Harness
Foot pedal

Check points

switch detected being OFF or foot pedal Normally Closed
Switch detected being ON.

3. Five flashes.

Movement at Error occurrence

Error Mode [Run Under Restrictions]:

The engine runs at a constant rotational speed.

Run restricted? Yes: The target speed is set to the "on-error target speed (standard value: 1500[min-1])"

or “pre-error target speed”.

Recovery

No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The wiring for the f oot pedal Normally Open switch ma y be disconnected.

• The wiring for the fo ot pedal Normally Closed switch ma y be short-circuited with GND .

• The foot pedal may be faulty.

• The inner wiring may be disconnected or short-circuited with GND .

• The E-ECU internal circuitry may be faulty.

1-20

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check that the foot pedal movement is correctly recognized.
*For details of the method and the procedure of diagnosis, see P.1-144

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the foot pedal is correctly inserted.

• Check that the wiring of the foot pedal is not disconnected or the insulation of
the wiring is not peeled.

• Check the foot pedal for correct continuity.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-144

TNV DI Service Manual

1-21

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Spare accelerator sensor (option)

(1) P0222/4: Failure with Spare Accelerator Sensor (Low Voltage)

DTC P0222/4 Failure with Spare Accelerator Se nsor (Low Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 0.2 [V] or lower.

Harness
Spare accelerator sensor

Check points

3. One flash followed by eight flashes

Movement at Error occurrence

Error detection of main accelerator sensor

Unavailable Available

Error Mode [Run As Is]:

The engine continues to run using the
main accelerator sensor.

[Run Under Restrictions]:
The engine runs at a constant rotational
speed.

Run restricted? No. Yes: The target speed is set to the "on-

error target speed (standard value:
1500[min

-1

])" or “pre-error target

speed”.

Recovery
Conditions

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The spare accelerator sensor's signal wires may be disconnected or short-circuited with GND .

• The SENSOR 5V wire may be disconnected o r short-circuited with GND.

• The SENSOR GND wire may be short-circuited with POWER SUPPLY (*NOTE).

*NOTE) If the SENSOR GND wire is short-circuited with PO WER SUPPL Y , the E-ECU's po wer supply line fuse

10A might be blown.With this fuse blown, the E-ECU may fail to detect/indicate the error , and to store
the error history.

• The spare accelerator sensor may be faulty.

• Sensor output defect by a disconnection of the spare accelerator sensor inner wiring or a sliding

resistance increase

• The E-ECU internal circuitry may be faulty.

1-22

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-148

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the spare accelerator sensor is correctly inserted.

• Check that the wiring of the spare accelerator sensor is not disconnect ed or the
insulation of the wiring is not peeled.

• Check the resistance value of the spare accelerator sensor.

• Check the harness for correct continuity.

• Check the output voltage of the spare accelerator sensor.

*For details of the method and the procedure of diagnosis, see P.1-148

TNV DI Service Manual

1-23

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P0223/3: Spare Accelerator Sensor Error (High Voltage)

DTC P0223/3 Spare Accelerator Sensor Error (High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 4.6 [V] or higher.

Harness
Spare accelerator sensor

Check points

3. One flash followed by eight flashes

Movement at Error occurrence

Error detection of main accelerator sensor

Unavailable Available

Error Mode [Run As Is]:

The engine continues to run using the
main accelerator sensor.

[Run Under Restrictions]:
The engine runs at a constant rotational
speed.

Run restricted? No. Yes: The target speed is set to the "on-

error target speed (standard value:

-1

1500[min

])" or “pre-error target

speed”.

Recovery
Conditions

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Yes: This error will be automatically reset

when a normal voltage (0.2 to

4.6[V]) is input.

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The SENSOR GND wire may be disconnected.

• The sensor signal wire may be short-circuited with POWER SUPPLY.

• The spare accelerator sensor may be faulty.

• Sensor output defect by a short circuit with power supply of the spare accelerator sensor inner wiring

• The E-ECU internal circuitry may be faulty.

1-24

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-148

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the spare accelerator sensor is correctly inserted.

• Check that the wiring of the spare accelerator sensor is not disconnect ed or the
insulation of the wiring is not peeled.

• Check the resistance value of the spare accelerator sensor.

• Check the harness for correct continuity.

• Check the output voltage of the spare accelerator sensor.

*For details of the method and the procedure of diagnosis, see P.1-148

TNV DI Service Manual

1-25

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P0224/2: Intermittent Failure with Spare Accelerator Sensor

DTC P0224/2 Intermittent Failure with Spare Accelerator Sensor

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Connector
Harness
Spare accelerator sensor

Check points

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• Spare accelerator sensor signal wire may be disconnected or short-circuited with GND or power supply.

• Sensor 5V wire may be disconnected, or short-circuited with GND or power supply.

• Sensor GND wire may be disconnected.

• The spare accelerator sensor may be faulty.

• Spare accelerator sensor wiring may be disconnected or short-circuited.

1-26

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-148

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the spare accelerator sensor is correctly inserted.

• Check that the wiring of the spare accelerator sensor is not disconnect ed or the
insulation of the wiring is not peeled.

• Check the resistance value of the spare accelerator sensor.

• Check the harness for correct continuity.

• Check the output voltage of the spare accelerator sensor.

*For details of the method and the procedure of diagnosis, see P.1-148

TNV DI Service Manual

1-27

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(4) P1225/1: Spare Accelerator Sensor Error (foot pedal-close position)

DTC P1225/1

Spare Accelerator Sensor Error (foot peda l-close
position)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. With sensor voltage at or below 0.65[V], foot pedal Normally

Harness
Foot pedal

Check points

Open switch detected being ON or foot pedal Normally Closed
Switch detected being OFF.

3. One flash followed by eight flashes

Movement at Error occurrence

Error detection of main accelerator sensor

Unavailable Available

Error Mode [Run As Is]:

The engine continues to run using the
main accelerator sensor.

[Run Under Restrictions]:
The engine runs at a constant rotational
speed.

Run restricted? No. Yes: The target speed is set to the "on-

error target speed (standard value:
1500[min

-1

])" or “pre-error target

speed”.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The wiring for the f oot pedal Normally Closed switch ma y be disconnected.

• The wiring for the f oot pedal Normally Open switch ma y be short-circuited with GND .

• The foot pedal may be faulty.

• The inner wiring may be disconnected or short-circuited with GND .

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check that the foot pedal movement is correctly recognized.
*For details of the method and the procedure of diagnosis, see P.1-144

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the foot pedal is correctly inserted.

• Check that the wiring of the foot pedal is not disconnected or the insulation of
the wiring is not peeled.

• Check the foot pedal for correct continuity.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-144

TNV DI Service Manual

1-29

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(5) P1226/0: Spare Accelerator Sensor Error (foot pedal-open position)

DTC P1226/0

Spare Accelerator Sensor Error (foot pedal-open
position)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. With sensor voltage 1.1[V] and above, foot pedal Normally Open

Harness
Foot pedal

Check points

switch detected being OFF or foot pedal Normally Closed
Switch detected being ON.

3. One flash followed by eight flashes

Movement at Error occurrence

Error detection of main accelerator sensor

Unavailable Available

Error Mode [Run As Is]:

The engine continues to run using the
main accelerator sensor.

[Run Under Restrictions]:
The engine runs at a constant rotational
speed.

Run restricted? No. Yes: The target speed is set to the "on-

error target speed (standard value:
1500[min

-1

])" or “pre-error target

speed”.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The wiring for the f oot pedal Normally Open switch ma y be disconnected.

• The wiring for the fo ot pedal Normally Closed switch ma y be short-circuited with GND .

• The foot pedal may be faulty.

• The inner wiring may be disconnected or short-circuited with GND .

• The E-ECU internal circuitry may be faulty.

1-30

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check that the foot pedal movement is correctly recognized.
*For details of the method and the procedure of diagnosis, see P.1-144

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the foot pedal is correctly inserted.

• Check that the wiring of the foot pedal is not disconnected or the insulation of
the wiring is not peeled.

• Check the foot pedal for correct continuity.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-144

TNV DI Service Manual

1-31

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(6) P1227/8: Failure with Spare Accelerator Sensor (Pulse Communication)

DTC P1227/8

Failure with Spare Accelerator Sensor (Pulse
Communication)

* This DTC is output when a pulse accelerator is used.

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

Harness

Check points

2. No pulse accelerator signal input

3. One flash followed by eight flashes

Movement at Error occurrence

CAN communication error detection

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine runs at a constant rotational
speed.

restrictions.

Run restricted? No. Yes: The target speed is set to the "on-

error target speed (standard value:
1500[min

-1

])" or “pre-error target

speed”.

Recovery
Conditions

Yes: The error is automatically reset

when a normal data is received.

Yes: The error is automatically reset

when a normal data is received.

Remarks

Estimation of Failure cause/Error condition

• Wiring defect of the harness

• The pulse accelerator's signal wires may be disconnected or short-circuited with GND .

• Source circuitry fault of the pulse accelerator signal

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.
*For details of the method and the procedure of diagnosis, see P.1-152

• Before beginning your work, be sure to turn off the key switch.

• Check that a source unit of the pulse accelerator signal and ECU are correctly
connected.

• Check that the wiring of the pulse accelerator signal is n ot disconnected or the
insulation of the wiring is not peeled.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-152

TNV DI Service Manual

1-33

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Atmospheric pressure sensor (option)

(1) P2228/4: Failure with Atmospheric Pressure Sensor (Low Voltage)

DTC P2228/4 Failure with Atmospheric Pressure Sens or (Low Vo ltage )

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 0.2 [V] or higher.

Harness
Atmospheric pressure sensor

Check points

3. One flash followed by nine flashes.

Movement at Error occurrence

Error Mode [Run Under Restrictions]:

The engine continues to run with the atmospheric pressu re u ncha nged from the pre-

error value.
Run restricted? Yes: The altitude compensation function is disabled.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The atmospheric pressure sensor's signal wires may be disconnected or short-circuited with GND.

• The SENSOR 5V wire may be disconnected o r short-circuited with GND.

• The SENSOR GND wire may be short-circuited with POWER SUPPLY (*NOTE).

*NOTE) If the SENSOR GND wire is short-circuited with PO WER SUPPL Y , the E-ECU's po wer supply line fuse

10A might be blown.With this fuse blown, the E-ECU may fail to detect/indicate the error , and to store
the error history.

• The atmospheric pressure sensor may be faulty.

• Sensor output defect by a disconnection of the atmospheric pressure sensor inner wiring or a sliding

resistance increase

• The E-ECU internal circuitry may be faulty.

1-34

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-148

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the atmospheric pressure sensor is correctly
inserted.

• Check that the wiring of the atmospheric pressure sensor is not disconnected
or the insulation of the wiring is not peeled.

• Check the resistance value of the atmospheric pressure sensor.

• Check the harness for correct continuity.

• Check the output voltage of the atmospheric pressure sensor.

*For details of the method and the procedure of diagnosis, see P.1-148

TNV DI Service Manual

1-35

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P2229/3: Failure with Atmospheric Pressure Sensor (High Voltage)

DTC P2229/3 Failure with Atmospheric Pressure Sensor ( High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 4.8 [V] or higher.

3. One flash followed by nine flashes.

Movement at Error occurrence

Error Mode [Run Under Restrictions]:

The engine continues to run with the atmospheric pressu re u ncha nged from the pre-

error value.
Run restricted? Yes: The altitude compensation function is disabled.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The SENSOR GND wire may be disconnected.

• The sensor signal wire may be short-circuited with POWER SUPPLY.

Check points

Harness
Atmospheric pressure sensor

• The atmospheric pressure sensor may be faulty.

• Sensor output defect by a short circuit with power supply of the atmospheric pressure sensor inner wiring

• The E-ECU internal circuitry may be faulty.

1-36

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-148

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the atmospheric pressure sensor is correctly
inserted.

• Check that the wiring of the atmospheric pressure sensor is not disconnected
or the insulation of the wiring is not peeled.

• Check the resistance value of the atmospheric pressure sensor.

• Check the harness for correct continuity.

• Check the output voltage of the atmospheric pressure sensor.

*For details of the method and the procedure of diagnosis, see P.1-148

TNV DI Service Manual

1-37

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P2230/2: Intermittent Failure with Atmospheric Pressure Sensor

DTC P2230/2 Intermittent Failure with Atmospheric Pressure Sensor

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Connector
Harness
Atmospheric pressure sensor

Check points

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• Accelerator sensor signal wire ma y be disconnected, or short-circuited with GND or power supply.

• Sensor 5V wire may be disconnected, or short-circuited with GND or power supply.

• Sensor GND wire may be disconnected.

• The atmospheric pressure sensor may be faulty.

• Inner wiring of atmospheric pressure sensor may be disconnected, or short circuited.

1-38

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-148

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the atmospheric pressure sensor is correctly
inserted.

• Check that the wiring of the atmospheric pressure sensor is not disconnected
or the insulation of the wiring is not peeled.

• Check the resistance value of the atmospheric pressure sensor.

• Check the harness for correct continuity.

• Check the output voltage of the atmospheric pressure sensor.

*For details of the method and the procedure of diagnosis, see P.1-148

TNV DI Service Manual

1-39

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

ECU Temperature Sensor

(1) P0668/4: Failure with ECU Temperature Sensor (Low Voltage)

DTC P0668/4 Failure with ECU Temperature Sensor (Low Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

E-ECU

2. Sensor voltage 1.0 [V] (at 140°C) or lower.

3. Four flashes followed by one flash.

Movement at Error occurrence

Error Mode [Operation Continuation]: No obstacles to control the engine.

The engine continues to run with the ECU temperature set to the default of 30[°C].
Run restricted? No.
Recovery

Conditions

Yes: This error will be automatically reset when a normal sensor voltage (1.0 to

4.6[V]) is input.

Remarks

Estimation of Failure cause/Error condition

• The E-ECU internal circuitry may be faulty.

Diagnosis Description

1) Initial diagnosis

with the diagnosis

• Check the fault indication.

• Check the ECU temperature.

tool

*For details of the method and the procedure of diagnosis, see P.1-154

Check points

1-40

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

(2) P0669/3: Failure with ECU Temperature Sensor (High Voltage)

DTC P0669/3 Failure with ECU Temperature Sensor (High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

E-ECU

2. Sensor voltage 4.6 [V] (at -45°C) or lower.

3. Four flashes followed by one flash.

Movement at Error occurrence

Error Mode [Operation Continuation]: No obstacles to control the engine.

The engine continues to run with the ECU temperature set to the default of 30 [°C].
Run restricted? No.
Recovery

Conditions

Yes: This error will be automatically reset when a normal sensor voltage (0.2 to

4.6[V]) is input.

Remarks

Estimation of Failure cause/Error condition

• The E-ECU internal circuitry may be faulty.

Diagnosis Description

1) Initial diagnosis

with the diagnosis

• Check the fault indication.

• Check the ECU temperature.

tool

*For details of the method and the procedure of diagnosis, see P.1-154

Check points

TNV DI Service Manual

1-41

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P1664/2: Intermittent Failure with ECU Temperature Sensor

DTC P1664/2 Intermittent Failure WITH ECU Temperature Sensor

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The E-ECU internal circuitry may be faulty.

Diagnosis Description

1) Initial diagnosis

with the diagnosis

• Check the fault indication.

• Check the ECU temperature.

tool

*For details of the method and the procedure of diagnosis, see P.1-154

Check points

E-ECU

1-42

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

(4) P0634/0: ECU Temperature Rise Alarm

DTC P0634/0 ECU Temperature Rise Alarm

DTC Detecting Conditions

FAILURE DIAGNOSIS

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

E-ECU

Check points

2. ECU internal temperature is 150 [°C] or higher.

3. Two flashes followed by five flashes.

Movement at Error occurrence

Setting of response to ECU temperature rise error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery
Conditions

Yes: This error is automatically reset

when the normal internal
temperature (under 100[°C]) of ECU
is detected.

Yes: This error is automatically reset

when the normal internal
temperature (under 100[°C]) of ECU
is detected.

Remarks

Estimation of Failure cause/Error condition

• The ambient temperature around the ECU may be too high.

• The E-ECU internal circuitry may be faulty.

TNV DI Service Manual

1-43

FAILURE DIAGNOSIS

Diagnosis Description

DTCs (Diagnostic Trouble Codes) General Description

1) Initial diagnosis

with the diagnosis

• Check the fault indication.

• Check the ECU temperature.

tool

*For details of the method and the procedure of diagnosis, see P.1-154

2) Engine Inspection • Turn the key switch off to stop the engine.

• Inspect around the E-ECU.

• After a little, turn the key switch on to check if the DTC is detected.
*For description and procedure of engine inspection, see the Service manual

(section “Engine”).

3) Failure Diagnostic

• Check the ECU temperature sensor.

Work

*For details of the method and the procedure of diagnosis, see P.1-154

1-44

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

Cooling water temperature sensor

(1) P0117/4: Failure with Cooling Water Temperature Sensor (Low Voltage)

DTC P0117/4

Failure with Cooling Water Temperature Sensor (Low
Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 0.2 [V] or lower.

3. Four flashes.

Movement at Error occurrence

In the case of a system with EGR In the case of a system without EGR

Error Mode [Run Under Restrictions]:

The engine continues to run under
restrictions.

The engine continues to run with the cooling water temperature set to the default of
30[°C].

Run restricted? Yes: The system restricts the High idle

speed or engine power.

Recovery

No. Yes: This error will be automatically reset

Conditions

Check points

Connector
Harness
Cooling water temperature sensor
E-ECU

[Run As Is]:

No.

when a normal sensor voltage (0.2
to 4.8[V]) is kept.

Remarks The restriction similar to one applied

against EGR errors is applied.

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The cooling water temperature sensor's sig nal wires may be short-circuited with GND .

• The cooling water temperature sensor's GND wire ma y be short-circuited with POWER SUPPLY.

• The cooling water temperature sensor may be faulty.

• Output defect of the cooling w ater temperature signal b y the inner wiring short-circuited with GND.

• The E-ECU internal circuitry may be faulty.

TNV DI Service Manual

1-45

FAILURE DIAGNOSIS

Diagnosis Description

DTCs (Diagnostic Trouble Codes) General Description

1) Initial diagnosis

with the diagnosis
tool

2) Check of

connectors/wiring

3) Failure Diagnostic

Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-156

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the cooling water temperature sensor is correctly
inserted.

• Check that the wiring of the cooling water temperature sensor is not
disconnected or the insulation of the wiring is not peeled.

• Check the resistance value of the cooling water temperature sensor.

• Check the harness for correct continuity.

• Check the output voltage of the cooling water temperature sensor.

*For details of the method and the procedure of diagnosis, see P.1-156

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

(2) P0118/3: Failure with Cooling Water Temperature Sensor (High Voltage)

DTC P0118/3

Failure with Cooling Water Temperature Sensor (High
Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Sensor voltage 4.8 [V] or higher.

3. Four flashes.

Movement at Error occurrence

In the case of a system with EGR In the case of a system without EGR

Error Mode [Run Under Restrictions]:

The engine continues to run under
restrictions.

The engine continues to run with the cooling water temperature set to the default of
30 [°C].

Run restricted? Yes: The system restricts the High idle

speed or engine power.

Check points

Connector
Harness
Cooling water temperature sensor
E-ECU

[Run As Is]:

No.

Recovery
Conditions

No. Yes: This error will be automatically reset

when a normal sensor voltage (0.2
to 4.8[V]) is kept.

Remarks The restriction similar to one applied

against EGR errors is applied.

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The cooling water temperature sensor's sig nal wires may be disconnected or short-circuited with

POWER SUPPLY .

• The cooling water temperature GND wire ma y be disconnected.

• The cooling water temperature sensor may be faulty.

• Output defect of the cooling w ater temperature signal b y the inner wiring disconnection

• The E-ECU internal circuitry may be faulty.

TNV DI Service Manual

1-47

FAILURE DIAGNOSIS

Diagnosis Description

DTCs (Diagnostic Trouble Codes) General Description

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-156

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the cooling water temperature sensor is correctly
inserted.

• Check that the wiring of the cooling water temperature sensor is not
disconnected or the insulation of the wiring is not peeled.

• Check the resistance value of the cooling water temperature sensor.

• Check the harness for correct continuity.

• Check the output voltage of the cooling water temperature sensor.

*For details of the method and the procedure of diagnosis, see P.1-156

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

(3) P0119/2: Intermittent Failure with Cooling Water Temperature Sensor

FAILURE DIAGNOSIS

DTC P0119/2

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any
restrictions.

Run restricted? No.
Recovery

No.

Conditions
Remarks

Intermittent Failure with Cooling Water Temperature
Sensor

Check points

Connector
Harness
High-accuracy cooling water
temperature sensor
E-ECU

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The cooling water temperature sensor's sig nal wires may be short-circuited with GND .

• The cooling water temperature sensor's sig nal wires may be disconnected or short-circuited with

POWER SUPPLY .

• GND wire of the cooling water temperature sensor may be disconnected.

• The cooling water temperature sensor may be faulty.

• Signal wire in the sensor may be disconnected, or short circuited.

• Sensor GND wire in the sensor may be disconnected.

TNV DI Service Manual

1-49

FAILURE DIAGNOSIS

Diagnosis Description

DTCs (Diagnostic Trouble Codes) General Description

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-156

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the cooling water temperature sensor is correctly
inserted.

• Check that the wiring of the cooling water temperature sensor is not
disconnected or the insulation of the wiring is not peeled.

• Check the resistance value of the cooling water temperature sensor.

• Check the harness for correct continuity.

• Check the output voltage of the cooling water temperature sensor.

*For details of the method and the procedure of diagnosis, see P.1-156

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

(4) P0217/0: Cooling Water Temperature Rise Alarm

DTC P0217/0 Cooling Water Temperature Rise Alarm

DTC Detecting Conditions

FAILURE DIAGNOSIS

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Cooling water temperature 115[°C] or higher.

3. Three flashes followed by six flashes.

Engine cooling water level
Engine cooling system
Cooling Water Temperature

Check points

Sensor

Movement at Error occurrence

Setting of response to cooling water temperature rise error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery
Conditions

Yes: This error is automatically reset

when the normal cooling water
temperature (under 110[°C]) is
detected.

Yes: This error is automatically reset

when the normal cooling water
temperature (under 110[°C]) is
detected.

Remarks

Estimation of Failure cause/Error condition

• The engine may be overheated.

• The engine cooling water level may be too low.

• The engine cooling system may be faulty.

• The cooling water temperature sensor may be faulty.

TNV DI Service Manual

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FAILURE DIAGNOSIS

Diagnosis Description

DTCs (Diagnostic Trouble Codes) General Description

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the cooling water temperature and the sensor voltage.
*For details of the method and the procedure of diagnosis, see P.1-156

• Turn the key switch off to stop the engine.

• Check the engine cooling system.

• After a little, turn the key switch on to check if the DTC is detected.
*For description and procedure of engine inspection, see the Service manual

(“Engine”).

• Check the cooling water temperature sensor system.
*For details of the method and the procedure of diagnosis, see P.1-156

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

SENSOR 5V

(1) P0642/4: Failure with SENSOR 5V (Low Voltage)

DTC P0642/4 Failure with SENSOR 5V (Low Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indicator Check points

1. Key switch ON.

2. SENSOR 5V monitoring voltage 4.5 [V] or lower.

Harness
E-ECU

3. Two flashes followed by four flashes.

Movement at Error occurrence

Error Mode [Operation Continuation]: After detecting the error, the system lets the engine

continue to run without any restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• Wiring defect of the harness

• The SENSOR 5V wire may be short-circuited with GND .

• The E-ECU internal circuitry may be faulty.

Diagnosis Description

1) Initial diagnosis

with the diagnosis
tool

• Check the fault indication.

• Check the voltage of the Sensor 5V .
*For details of the method and the procedure of diagnosis, see P.1-160

2) Check of

connectors/wiring

3) Failure Diagnostic

Work

TNV DI Service Manual

• Before beginning your work, be sure to turn off the key switch.

• Check that the insulation of the Sensor 5V is not peeled.

• Check the harness for correct continuity.

• Check the output voltage of the E-ECU (voltage of the sensor 5V line).
*For details of the method and the procedure of diagnosis, see P.1-160

1-53

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P0643/3: Failure with SENSOR 5V (High Voltage)

DTC P0643/3 Failure with SENSOR 5V (High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. SENSOR 5V monitoring voltage 5.5 [V] or higher.

Harness
E-ECU

3. Two flashes followed by four flashes.

Movement at Error occurrence

Error Mode [Run As Is]:After detecting the error, the system lets the engine continue to run

without any restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• Wiring defect of the harness

• The SENSOR GND wire may be disconnected.

• The SENSOR 5V wire may be short-circuited with POWER SUPPLY.

• The E-ECU internal circuitry may be faulty.

Diagnosis Description

1) Initial diagnosis

with the diagnosis
tool

2) Check of

connectors/wiring

• Check the fault indication.

• Check the voltage of the Sensor 5V .
*For details of the method and the procedure of diagnosis, see P.1-160

• Before beginning your work, be sure to turn off the key switch.

• Check that the Sensor 5V line and sensor GND line are not disconnected or the
insulation of the wiring is not peeled.

3) Failure Diagnostic
Work

1-54

• Check the harness for correct continuity.

• Check the output voltage of the E-ECU (voltage of the sensor 5V line).
*For details of the method and the procedure of diagnosis, see P.1-160

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

FAILURE DIAGNOSIS

(3) P1644/2: Intermittent Failure with SENSOR 5V

DTC P1644/2 Intermittent Failure with SENSOR 5V

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indicator Check points

1. Engine running.

2. Unconfirmed error detected 10 times.

Harness
E-ECU

3: Does not flash.

Movement at Error occurrence

Error Mode [Operation Continuation]: After detecting the error, the system lets the engine

continue to run without any restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• Wiring defect of the harness

• The SENSOR 5V wire may be short-circuited with power supply or GND.

• Sensor GND wire may be disconnected.

• The E-ECU internal circuitry may be faulty.

Diagnosis Description

1) Initial diagnosis

with the diagnosis
tool

2) Check of

connectors/wiring

• Check the fault indication.

• Check the voltage of the Sensor 5V .
*For details of the method and the procedure of diagnosis, see P.1-160

• Before beginning your work, be sure to turn off the key switch.

• Check that the Sensor 5V line and sensor GND line are not disconnected or the
insulation of the wiring is not peeled.

3) Failure Diagnostic
Work

TNV DI Service Manual

• Check the harness for correct continuity.

• Check the output voltage of the E-ECU (voltage of the sensor 5V line).
*For details of the method and the procedure of diagnosis, see P.1-160

1-55

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Power supply Voltage

(1) P0562/1: Power Supply Voltage Error (Low Voltage)

DTC P0562/1 Power Supply Voltage Error (Low Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. E-ECU supply voltage below 10[V]

3. Two flashes followed by three flashes.

Movement at Error occurrence

Error Mode [Operation Continuation]: After detecting the error, the system lets the engine

continue to run without any restrictions.

Run restricted? No.

Battery
alternator
Harness

Recovery
Conditions

Yes: This error will be automatically reset when a normal supply voltage (10 to 16[V])

is input.

Remarks

Estimation of Failure cause/Error condition

• The battery may be deteriorated.

• The battery connection may be miswired.

• The alternator may be faulty.

• The harness may be disconnected or short-circuited.

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis

• Check the fault indication.

• Check the battery voltage.

tool

2) Engine Inspection • Turn the key switch off to stop the engine.

• Check the battery voltage using a circuit tester.

• Inspect the charging system of the engine .

• After a little, turn the key switch on to check if the DTC is detected.
*For description and procedure of engine inspection, see the Service manual

(“Engine”).

3) Failure Diagnostic
Work

• Check that the battery wiring is not disconnected or the insulation of the wiring
is not peeled.

TNV DI Service Manual

1-57

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P0563/0: Power Supply Voltage Error (High Voltage)

DTC P0563/0 Power Supply Voltage Error (High Voltage)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. E-ECU supply voltage over 16[V]

3. Two flashes followed by three flashes.

Battery
alternator
Harness

Movement at Error occurrence

Error Mode [Operation Continuation]: After detecting the error, the system lets the engine

continue to run without any restrictions.
Run restricted? No.
Recovery

Conditions

Yes: This error will be automatically reset when a normal supply voltage (10 to 16[V])

is input.

Remarks

Estimation of Failure cause/Error condition

• An incompatible battery (such as a 24V battery) may be used.

• The battery connection may be miswired.

• The alternator may be faulty.

• The harness may be disconnected or short-circuited.

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis

• Check the fault indication.

• Check the battery voltage.

tool

2) Engine Inspection • Turn the key switch off to stop the engine.

• Check the battery voltage using a circuit tester.

• Inspect the charging system of the engine .

• After a little, turn the key switch on to check if the DTC is detected.
*For description and procedure of engine inspection, see the Service manual

(“Engine”).

3) Failure Diagnostic
Work

• Check that the battery wiring is not disconnected or the insulation of the wiring
is not peeled.

TNV DI Service Manual

1-59

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Pulse Sensor Related Failures

Speed Sensor

(1) P0340/4: Failure with Speed Sensor

DTC P0340/4 Speed Sensor Error

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch START, engine running.

2. Speed sensor signal 0[min

-1

]

3. Six flashes.

Movement at Error occurrence

Spare speed sensor setting

Unavailable Available

Error Mode [Stop Immediately]:

The engine stops running.

Run restricted? Yes: The rack actuator relay is turned

OFF, and the rack position is forcibly
set to the engine stop position.

Recovery

Yes: Key switch START Yes: Key switch START
Conditions
Remarks

[Run Under Restrictions]:
The engine continues to run under
restrictions with the spare speed sensor
used instead.

Yes: The system restricts the High idle

speed or engine power.

Connector
Harness
Speed Sensor
E-ECU

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Engine speed defect

• Battery voltage descent at cold start etc.

• Starter system failure

• Fuel injection not availab le (fuel freezing)

• Engine locked (seizure , freezing)

• Battery voltage descent (over discharge , deterioration)

• Load increase driven by the opera ting machine

• Wiring defect of the harness

• The speed sensor's signal wires (+) and (-) may be disconnected or short-circuited with GND .

• The starter signal wire may be short-circuited with POWER SUPPLY.

• The speed sensor may be faulty.

• Output defect of the speed signa l by a disconnection or a short circuit of the inner wiring

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the engine speed.
*For details of the method and the procedure of diagnosis, see P.1-164

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the speed sensor is correctly inserted.

• Check that the wiring of the speed sensor is not disconnected or the insulation
of the wiring is not peeled.

• Check the resistance value of the speed sensor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-164

TNV DI Service Manual

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FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Spare speed sensor (option)

(1) P1340/4: Failure with Spare Speed Sensor

DTC P1340/4 Failure with Spare Speed Sensor

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. Spare speed sensor signal below 0[min

3. One flash followed by another flash.

Movement at Error occurrence

Unavailable Available

-1

].

Main speed sensor error detection

Connector
Harness
alternator
E-ECU

Error Mode [Run As Is]:

After detecting the error, the system lets

[Stop Immediately]:

The engine stops running.
the engine continue to run without any
restrictions.

Run restricted? No. Yes: The rack actuator relay is turned

OFF, and the rack position is forcibly
set to the engine stop position.

Recovery

No. Yes:Key switch START

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Output pulse voltage defect by low engine speed

• Output pulse defect by the battery over-charge

• Wiring defect of the harness

• The spare speed sensor's signal wires may be disconnected or short-circuited with GND .

• The alternator's terminals B and IG may be disconnected or short-circuited with GND.

• Output pulse defect by the alternator failure

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the rotational speed of the spare speed sensor.
*For details of the method and the procedure of diagnosis, see P.1-167

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the alternator is correctly inserted.

• Check that the wiring of the alternator is not disconnected or the insulation of
the wiring is not peeled.

• Check the battery voltage.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-167

TNV DI Service Manual

1-63

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Engine rotational speed

(1) P0219/0: Over speed error

DTC P0219/0 Overspeed Error

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. Sensor signal at or above the upper limit (High idle speed +600[min

-1

]).

3. Two flashes followed by five flashes.

Movement at Error occurrence

Error Mode [Stop Immediately]: The engine stops running.
Run restricted? Yes: The rack actuator relay is turned OFF, and the rack position is forcibly set to the

engine stop position.

Harness
Speed Sensor
Rack actuator
E-ECU

Recovery

No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• Wiring defect of the harness

• The rack actuator wiring ma y be short-circuited with GND.

• False generation of speed sensor signal pulse

• False wiring of the speed sensor

• Engine over speed loaded by the operating machine’s drive

• Control error of the fuel injection pump

• The rack actuator wiring ma y be short-circuited with GND.

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis

• Check the fault indication.

with the diagnosis
tool

2) Engine Inspection • Turn the key switch off to stop the engine.

• Inspect the engine and the operating machine.

• After a little, turn the key switch on to check if the DTC is detected.

*For description and procedure of engine inspection, see the Service manual

(“Engine”).

3) Failure Diagnostic

• Check the Rack Actuator.

Work

*For details of the method and the procedure of diagnosis, see P.1-167

TNV DI Service Manual

1-65

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Contact Output Related Failures

Rack actuator Relay

(1) P1222/4: Failure A with Rack Actuator Relay

DTC P1222/4 Failure A with Rack Actuator Relay

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects the rack actuator
relay turning ON during the command to turn OFF the rack actuator relay.

3. One flash followed by seven flashes.

Movement at Error occurrence

Error Mode [Stop Immediately]: The engine stops running.
Run restricted? Yes: The rack actuator relay is turned OFF, and the rack position is forcibly set to the

engine stop position.

Connector
Harness
Rack actuator Relay
E-ECU

Recovery

No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The rack actuator rela y wiring may be disconnected or short-circuited with GND .

• The rack actuator relay may be faulty.

• Inner wiring disconnection

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the rack actuator relay.

• Check the movement of the rack actuator relay by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-170

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the rack actuator relay is correctly inserted.

• Check that the wiring of the rack actuator relay is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the rack actuator relay.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-170

TNV DI Service Manual

1-67

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P1223/3: Failure B with Rack Actuator Relay

DTC P1223/3 Failure B with Rack Actuator Relay

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects the rack actuator
relay turning OFF during the command to turn ON the rack actuator relay.

3. One flash followed by seven flashes.

Connector
Harness
Rack actuator Relay
E-ECU

Movement at Error occurrence

Error Mode [Stop Immediately]: The engine stops running.
Run restricted? Yes: The rack actuator relay is turned OFF, and the rack position is forcibly set to the

engine stop position.

Recovery

No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• Wiring defect of the harness

• The rack actuator rela y wiring may be short-circuited with POWER SUPPLY (*NOTE).

• The rack actuator relay may be faulty.

• Inner wiring short-circuited with POWER SUPPLY (*NOTE).

*NOTE) If the rack actuator rela y wire is short-circuited with POWER SU PPL Y , inner circuit of E-ECU may fail

before the E-ECU's power suppl y line fuse 10A is blown.I n this case, the ECU fails to detect/indicate
the error , and to store t he error history.

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the rack actuator relay.

• Check the movement of the rack actuator relay by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-170

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the rack actuator relay is correctly inserted.

• Check that the wiring of the rack actuator relay is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the rack actuator relay.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-170

TNV DI Service Manual

1-69

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P1224/2: Intermittent Failure with Rack Actuator Relay

DTC P1224/2 Intermittent Failure with Rack Actuator Relay

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The rack actuator rela y wiring may be disconnected or short-circuited with GND .

• The E-ECU internal circuitry may be faulty.

Connector
Harness
Rack actuator Relay
E-ECU

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the rack actuator relay.

• Check the movement of the rack actuator relay by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-170

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the rack actuator relay is correctly inserted.

• Check that the wiring of the rack actuator relay is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the rack actuator relay.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-170

TNV DI Service Manual

1-71

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

Start Assist Relay

(1) P1232/4: Failure A with Start Assist Relay

DTC P1232/4 Failure A with Start Assist Relay

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. Make an assessment logically a s to followings.E-ECU detects the start assist
relay turning ON during the command to turn OFF the start assist relay.

3. One flash followed by five flashes.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Connector
Harness
Start Assist Relay
E-ECU

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The start assist relay wiring may be disconnected or short-circuited with POWER SUPPLY .

• The start assist relay may be faulty.

• Disconnection of Start Assist Relay inner wiring

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the start assist relay.

• Check the movement of the start assist relay by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-174

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the start assist relay is correctly inserted.

• Check that the wiring of the start assist relay is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the start assist relay.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-174

TNV DI Service Manual

1-73

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P1233/3: Failure B with Start Assist Relay

DTC P1233/3 Failure B with Start Assist Relay

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. Make an assessment logically a s to followings.E-ECU detects the start assist
relay turning OFF during the command to turn ON the start assist relay.

3. One flash followed by five flashes.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The start assist relay wiring may be short-circuited with GND (*NOTE).

• The start assist relay may be faulty.

• Inner wiring of the start assist relaymay be short-circuited with GND (*NOTE).

Connector
Harness
Start Assist Relay
E-ECU

*NOTE) If the start assist relay wire is short-circuited with GND, the E-ECU's power supply line fuse 10A

might be blown.Also the E-ECU internal circuitry may be faulty.In this case, the E-ECU may fail to
detect/indicate the err or , and to store the err or history .

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the start assist relay.

• Check the movement of the start assist relay by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-174

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the start assist relay is correctly inserted.

• Check that the wiring of the start assist relay is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the start assist relay.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-174

TNV DI Service Manual

1-75

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P1234/2: Intermittent Failure with Start Assist Relay

DTC P1234/2 Intermittent Failure with Start Assist Relay

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Connector
Harness
Start Assist Relay
E-ECU

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The start assist relay wiring may be disconnected or short-circuited with POWER SUPPLY .

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the start assist relay.

• Check the movement of the start assist relay by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-174

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the start assist relay is correctly inserted.

• Check that the wiring of the start assist relay is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the start assist relay.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-174

TNV DI Service Manual

1-77

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

CSD solenoid valve

(1) P1242/4: Failure A with CSD solenoid valve

DTC P1242/4 Failure A with CSD Solenoid Valve

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects the CSD
solenoid valve turning ON signal during the command to turn OFF the CSD
solenoid valve.

3. One flash followed by four flashes.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Connector
Harness
CSD solenoid valve
E-ECU

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• CSD solenoid valve wiring may be disconnected or short-circuited with POWER SUPPLY.

• The CSD solenoid valve may be faulty.

• Inner wiring disconnection

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the CSD solenoid valve.

• Check the movement of the CSD solenoid valve by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-178

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the CSD solenoid valve is correctly inserted.

• Check that the wiring of the CSD solenoid valve is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the CSD solenoid valve coil.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-178

TNV DI Service Manual

1-79

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P1243/3: Failure B with CSD solenoid valve

DTC P1243/3 Failure B with CSD Solenoid Valve

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects the CSD
solenoid valve turning OFF signal during the command to turn ON the CSD
solenoid valve.

3. One flash followed by four flashes.

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The CSD solenoid valve wiring may be short-circuited with GND (*NOTE).

• The CSD solenoid valve may be faulty.

• Inner wiring short-circuited with GND (*NOTE).

Connector
Harness
CSD solenoid valve
E-ECU

*NOTE) If the CSD solenoid v alve wire i s short-circuite d with GND , the E-ECU's po wer supply li ne fuse 10A

might be blown.Also the E-ECU internal circuitry may be faulty.In this case, the E-ECU may fail to
detect/indicate the err or , and to store the err or history .

• The E-ECU internal circuitry may be faulty.

1-80

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the CSD solenoid valve.

• Check the movement of the CSD solenoid valve by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-178

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the CSD solenoid valve is correctly inserted.

• Check that the wiring of the CSD solenoid valve is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the CSD solenoid valve coil.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-178

TNV DI Service Manual

1-81

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P1244/2: Intermittent Failure with CSD solenoid valve

DTC P1244/2 Intermittent Failure with CSD solenoid valve

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s); 3 - Flashing pattern of failure indica tor Check points

1. Engine running.

2. Unconfirmed error detected 10 times.
3: Does not flash.

Connector
Harness
CSD solenoid valve
E-ECU

Movement at Error occurrence

Error Mode [Run As Is]:

After detecting the error, the system lets the engine continue to run without any

restrictions.
Run restricted? No.
Recovery

No.
Conditions

Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The CSD solenoid valve wiring may be disconnected or short-circuited with POWER SUPPLY .

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the CSD solenoid valve.

• Check the movement of the CSD solenoid valve by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-178

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the CSD solenoid valve is correctly inserted.

• Check that the wiring of the CSD solenoid valve is not disconnected or the
insulation of the wiring is not peeled.

• Check the resistance value of the CSD solenoid valve coil.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-178

TNV DI Service Manual

1-83

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

EGR valve

(1) P1402/4: Failure A with EGR valve (Step Motor A-phase)

DTC P1402/4 Failure A with EGR valve (Step Motor A-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor A-phase turning ON during the command to
turn OFF the EGR step motor A-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor A-phase wiring may be disconnected or short-circuited with GND .

• The EGR step motor power supply line ma y be disconnected.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor A-phase may be disconnected or short-circuited with GND .

• Po wer supply line in the EGR step motor ma y be disconnected.

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

TNV DI Service Manual

1-85

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(2) P1403/3: Failure B with EGR valve (Step Motor A-phase)

DTC P1403/3 Failure B with EGR valve (Step Motor A-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor A-phase turning OFF during the command
to turn ON the EGR step motor A-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor A-phase wiring may be short-circuited with POWER SUPPLY.

• The EGR step motor wiring may be short-circuited between phases.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor A-phase may be short-circuited with POWER SUPPLY.

• Inner wiring of the EGR step motor may be short-circuited between phases.

• The E-ECU internal circuitry may be faulty.

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TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

TNV DI Service Manual

1-87

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(3) P1412/4: Failure A with EGR valve (Step Motor B-phase)

DTC P1412/4 Failure A with EGR valve (Step Motor B-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor B-phase turning ON during the command to
turn OFF the EGR step motor B-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor B-phase wiring may be disconnected or short-circuited with GND .

• The EGR step motor power supply line ma y be disconnected.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor B-phase may be disconnected or short-circuited with GND .

• Po wer supply line in the EGR step motor ma y be disconnected.

• The E-ECU internal circuitry may be faulty.

1-88

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

TNV DI Service Manual

1-89

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(4) P1413/3: Failure B with EGR valve (Step Motor B-phase)

DTC P1413/3 Failure B with EGR valve (Step Motor B-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor B-phase turning OFF during the command
to turn ON the EGR step motor B-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor B-phase wiring may be short-circuited with POWER SUPPLY.

• The EGR step motor wiring may be short-circuited between phases.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor B-phase may be short-circuited with POWER SUPPLY.

• Inner wiring of the EGR step motor may be short-circuited between phases.

• The E-ECU internal circuitry may be faulty.

1-90

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

TNV DI Service Manual

1-91

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(5) P1422/4: Failure A with EGR valve (Step Motor C-phase)

DTC P1422/4 Failure A with EGR valve (Step Motor C-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor C-phase turning ON during the command
to turn OFF the EGR step motor C-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor C-phase wiring may be disconnected or short-circuited with GND .

• The EGR step motor power supply line ma y be disconnected.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor C-phase may be disconnected or short-circuited with GND .

• Po wer supply line in the EGR step motor ma y be disconnected.

• The E-ECU internal circuitry may be faulty.

1-92

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

TNV DI Service Manual

1-93

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(6) P1423/3: Failure B with EGR valve (Step Motor C-phase)

DTC P1423/3 Failure B with EGR valve (Step Motor C-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor C-phase turning OFF during the command
to turn ON the EGR step motor C-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor C-phase wiring may be short-circuited with POWER SUPPLY.

• The EGR step motor wiring may be short-circuited between phases.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor C-phase may be short-circuited with POWER SUPPLY.

• Inner wiring of the EGR step motor may be short-circuited between phases.

• The E-ECU internal circuitry may be faulty.

1-94

TNV DI Service Manual

DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

TNV DI Service Manual

1-95

FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(7) P1432/4: Failure A with EGR valve (Step Motor D-phase)

DTC P1432/4 Failure A with EGR valve (Step Motor D-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings. E-ECU detects
the EGR step motor D-phase turning ON during the command
to turn OFF the EGR step motor C-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor D-phase wiring may be disconnected or short-circuited with GND .

• The EGR step motor power supply line ma y be disconnected.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor D-phase may be disconnected or short-circuited with GND .

• Po wer supply line in the EGR step motor ma y be disconnected.

• The E-ECU internal circuitry may be faulty.

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DTCs (Diagnostic Trouble Codes) General Description

Diagnosis Description

FAILURE DIAGNOSIS

1) Initial diagnosis
with the diagnosis
tool

2) Check of
connectors/wiring

3) Failure Diagnostic
Work

• Check the fault indication.

• Check the output signal of the EGR step motor.

• Check the movement of the EGR step motor by the active control function.
*For details of the method and the procedure of diagnosis, see P.1-182

• Before beginning your work, be sure to turn off the key switch.

• Check that the connector of the EGR step motor is correctly inserted.

• Check that the wiring of the EGR step motor is not disconnected or the
insulation of the wiring is not peeled.

• Check the coil resistance of the EGR step motor.

• Check the harness for correct continuity.

*For details of the method and the procedure of diagnosis, see P.1-182

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FAILURE DIAGNOSIS

DTCs (Diagnostic Trouble Codes) General Description

(8) P1433/3: Failure B with EGR valve (Step Motor D-phase)

DTC P1433/3 Failure B with EGR valve (Step Motor D-Phase)

DTC Detecting Conditions

1 - Precondition; 2 - Detecting condition(s);
3 - Flashing pattern of failure indicator

1. Key switch ON.

2. Make an assessment logically as to followings.E-ECU detects
the EGR step motor D-phase turning OFF during the command
to turn ON the EGR step motor D-phase.

Connector
Harness
EGR valve (step motor)
E-ECU

Check points

3. One flash followed by three flashes.

Movement at Error occurrence

Movement setting at the EGR step motor error

Unavailable Available

Error Mode [Run As Is]:

After detecting the error, the system lets
the engine continue to run without any

[Run Under Restrictions]:
The engine continues to run under
restrictions.

restrictions.

Run restricted? No. Yes: The system restricts the High idle

speed or engine power.

Recovery

No. No.

Conditions
Remarks

Estimation of Failure cause/Error condition

• The connector may not be properly connected.

• Wiring defect of the harness

• The EGR step motor D-phase wiring may be short-circuited with POWER SUPPLY.

• The EGR step motor wiring may be short-circuited between phases.

• The EGR step motor may be faulty.

• Inner wiring of the EGR step motor D-phase may be short-circuited with POWER SUPPLY.

• Inner wiring of the EGR step motor may be short-circuited between phases.

• The E-ECU internal circuitry may be faulty.

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