Hino N04C-T Service Manual

Diesel Injection Pump

SERVICE MANUAL

Common Rail System for HINO Dutro / TOYOTA Dyna N04C-T# Type Engine

OPERATION

November, 2003

00400058E

		TABLE OF CONTENTS
1.	Product Application List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		1
	1-1.	Vehicle Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	1
	1-2.	Component Part Numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	1
2.	Common Rail System Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		2
	2-1.	Background to Development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	2
	2-2.	System Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	2
	2-3. Comparison to The Conventional System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		3
3.	Outline of TOYOTA / HINO Small Truck Common Rail System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		4
	3-1.	Main System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	4
	3-2. Outline of Composition and Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		5
	3-3. Fuel System and Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		6
4.	Description of Main Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		7
	4-1.	Supply Pump (HP3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	7
	4-2.	Rail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	14
	4-3.	Injector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	16
	4-4. Engine ECU (Electronic Control Unit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		19
	4-5. EDU (Electronic Driving Unit) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		19
5.	Description of Control System Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		20
	5-1.	Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	20
	5-2.	Description of Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	21
6.	Various Types of Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		26
	6-1. Common Rail System Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		26
	6-2. Fuel Injection Quantity Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		27
	6-3. Fuel Injection Timing Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		30
	6-4. Fuel Injection Rate Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		31
	6-5. Fuel Injection Pressure Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		31
7.	Other (ECU Related) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		32
	7-1. ECU External Wiring and Terminal Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .		32
	7-2.	Diagnostic Trouble Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	38

1.		Product Application List
1-1.		Vehicle Specifications
		Vehicle Name	Engine Model	Exhaust Volume
		HINO DUTRO / TOYOTA DYNA	N04C-TF	4.0L
1-2. Component Part Numbers
		Product Name	HINO Part Number	DENSO Part Number
	Supply Pump		22730-1261B	294000-0191
	Rail		22760-1170A	095440-0490
	Injector		23910-1271A	095000-5321
	Engine ECU		89660-37460	101758-6580
	EDU		89870-37030	101310-5391
	APM (Accelerator Pedal Module)		78100-37550	198800-3150
	NE Sensor		89411-1630A	029600-1361
	TDC Sensor		89410-1570A	949979-1310
	Coolant Temperature Sensor		83420-1250A	071560-0110
	AFM (Mass Airflow Meter)		22204-21010	197400-2000
	Intake Air Temperature Sensor		89441-4310A	071500-2490
	Turbo Pressure Sensor		89390-1080A	079800-5890
	EGR-V		17350-1170A	135000-7051
	Exhaust Gas Temperature Sensor		89441-37020 (IN)	265600-0600 (IN)
			89441-37030 (OUT)	265600-0530 (OUT)

-1-

2. Common Rail System Outline

2-1. Background to Development

•The common rail system was developed primarily to cope with exhaust gas regulations for diesel engines, and is a diesel injection control system with the following aims:

•To further improve fuel economy;

•To reduce noise;

•To achieve high power output.

2-2. System Characteristics

•The common rail system uses a type of accumulation chamber called a rail to store pressurized fuel, and injectors that contain electronically controlled solenoid valves to inject the pressurized fuel into the cylinders. Because the engine ECU controls the injection system (injection pressure, injection rate, and injection timing), the injection system is independent, and thus unaffected by the engine speed or load. This ensures a stable injection pressure at all times, particularly in the low engine speed range, and dramatically decreases the amount of black smoke ordinarily emitted by a diesel engine during start-up and acceleration. As a result, exhaust gas emissions are cleaner and reduced, and higher power output is achieved.

A.Injection Pressure Control

•Enables high-pressure injection even at low engine speeds.

•Optimizes control to minimize particulate matter and NOx emissions.

B.Injection Timing Control

•Enables finely tuned optimized control in accordance with driving conditions.

C.Injection Rate Control

•Pilot injection control injects a small amount of fuel before the main injection.

			Common Rail System
		Injection Pressure Control			Injection Timing Control	Injection Rate Control
		Optimization, High Pressurization			Optimization	Rate	Pilot	After-Injection
							Injection
										Post-Injection
	Injection Pressure	Common Rail System			Common Rail	Injection		Main
					System
							Injection
			Particulate
				NOx			Crankshaft Angle
							Injection Quantity Control
		Conventional			Conventional		Cylinder Injection
							Quantity Correction
		Pump			TimingInjection
					Pump
		Speed	Injection Pressure		Speed	Speed
							1	3	4	2
										Q000518E
					-2-

2-3. Comparison to The Conventional System
	In-Line & VE Pumps		Common Rail System
	High-Pressure Pipe
	Momentary High Pressure		Supply	Rail
	Timer		Pump
		Nozzle		Normally High Pressure
	Governor
System				Delivery Valve
	In-Line Pump
			Feed	SCV (Suction Control Valve)
			Pump
				Injector
			Fuel Tank
	VE Pump
Injection Quantity Control	Pump (Governor)		Engine ECU, Injector (TWV)*1
Injection Timing Control	Pump (Governor)		Engine ECU, Injector (TWV)*1
Rising Pressure	Pump		Engine ECU, Supply Pump
Distributor	Pump			Engine ECU, Rail
Injection Pressure Control	Dependent upon speed and injection quantity		Engine ECU, Supply Pump (SCV)*2
				*1 TWV: Two Way Valve
				*2 SCV: Suction Control Valve
				Q000387E

-3-

3. Outline of TOYOTA / HINO Small Truck Common Rail System

3-1. Main System Components

	Accelerator Position Sensor
Intake Air Temperature Sensor
Variable Nozzle Type Turbo Opening Sensor	Intake Air Pressure Sensor
Variable Nozzle Type Turbo Motor	EGR Valve
	Intake Restriction
Glow Plug	Step Motor
Airflow Meter (With Integrated Ambient
Air Temperature Sensor)
	Variable Nozzle
Injector	Controller
Crankshaft Position Sensor
Rail Pressure Sensor	Pressure Limiter
	Engine ECU (With
	Built-In Atmospheric
	Pressure Sensor)
	EDU
	Coolant Temperature Sensor
Cylinder Recognition Sensor
	Rail
Supply Pump
SCV
Fuel Temperature Sensor	Items are DENSO products
	Q000569E
-4-

3-2. Outline of Composition and Operation A. Composition

The common rail system consists primarily of a supply pump, rail, injectors, and engine ECU.

Fuel Temperature

Vehicle Speed

Accelerator Opening

Intake Air Pressure

Intake Air Temperature Engine ECU

Coolant Temperature

Crankshaft Position

Cylinder Recognition Signal

	Intake Airflow Rate
	Rail	Pressure	Injector
		Limiter
	Rail
	Pressure Sensor

Fuel Temperature Sensor

	Supply Pump	SCV (Suction	Fuel Tank
		Control Valve)

Q000144E

B. Operation

a.Supply Pump (HP3)

The supply pump draws fuel from the fuel tank, and pumps the high pressure fuel to the rail. The quantity of fuel discharged from the supply pump controls the pressure in the rail. The SCV (Suction Control Valve) in the supply pump effects this control in accordance with commands received from the engine ECU.

b.Rail

The rail is mounted between the supply pump and the injector, and stores the high-pressure fuel.

c.Injector (G2 Type)

This injector replaces the conventional injection nozzle, and achieves optimal injection by effecting control in accordance with signals from the engine ECU. Signals from the engine ECU determine the duration and timing in which current is applied the injector. This in turn, determines the quantity, rate and timing of the fuel that is injected from the injector. QR codes noting the characteristics of each vehicle are inscribed on the injector, and this data is sent to the ECU when the engine ECU or injectors are replaced. This enables software to be adjusted to the mechanical characteristics of each injector.

d.Engine ECU

The engine ECU calculates data received from the sensors to comprehensively control the injection quantity, timing and pressure.

-5-

3-3. Fuel System and Control System A. Fuel System

This system comprises the route through which diesel fuel flows from the fuel tank via the rail to the supply pump, and is injected through the injector, as well as the route through which the fuel returns to the tank via the overflow pipe.

B. Control System

In this system, the engine ECU controls the fuel injection system in accordance with signals received from various sensors. The components of this system can be broadly divided into the following three types: (a) sensors; (b) ECU; and (c) actuators.

a.Sensors

Detect the engine and driving conditions, and convert them into electrical signals.

b.Engine ECU

Performs calculations based on the electrical signals received from the sensors, and sends them to the actuators in order to achieve optimal conditions.

c.Actuators

Operate in accordance with electrical signals received from the ECU. Injection system control is undertaken by electronically controlling the actuators. The injection quantity and timing are determined by controlling the duration and timing in which current is applied to the TWV (Two-Way Valve) in the injector. Injection pressure is determined by controlling the SCV (Suction Control Valve) in the supply pump.

	Sensor						Actuator
	Crankshaft Position Sensor NE	Engine Speed
							Injector
							· Injection Quantity Control
		Cylinder Recognition					· Injection Timing Control
	Cylinder Recognition Sensor G						· Injection Pressure Control
		Load		Engine
	Accelerator Position Sensor
				ECU			Supply Pump (SCV)
							· Fuel Pressure Control
	Rail Pressure Sensor
							EGR, Air Intake Control
							Relay, Light
	Other Sensors and Switches
							Q000390E

-6-

4. Description of Main Components

4-1. Supply Pump (HP3)

A.Outline

•The supply pump consists primarily of the pump body (camshaft (eccentric cam), ring cam, and plungers), SCV (Suction Control Valve), fuel temperature sensor, and feed pump.

SCV

Fuel Temperature Sensor

Q000570E

•The two plungers are positioned vertically on the outer ring cam for compactness.

•The engine drives the supply pump at a ratio of 1:1. The supply pump has a built-in feed pump (trochoid type), and draws the fuel from the fuel tank, sending it to the plunger chamber.

•The internal camshaft drives the two plungers, and they pressurize the fuel sent to the plunger chamber and send it to the rail. The quantity of fuel supplied to the rail is controlled by the SCV, using signals from the engine ECU. The SCV is a normally open type (the intake valve opens during de-energization).

Injector	Rail	Intake Valve				Intake Pressure
		Discharge Valve				Feed Pressure
		Plunger				High Pressure
						Return
						Return Spring
	Return
	Fuel Overflow					SCV
						Regulating Valve
						Feed Pump
		Filter
		Camshaft				Fuel Inlet
Fuel Tank						Intake Fuel Filter
						(With Priming Pump)
						Q000392E

• The supply pump in the common rail system with DPNR has a fuel cut valve (FCV). The FCV is provided to enable manual shut-off if a fuel leak occurs in the fuel addition valve passage.

-7-

a.Supply Pump Exploded Diagram

	SCV
	(Suction Control Valve)
	Plunger
Pump Body	Feed Pump
Ring Cam	Regulating Valve
	Filter
Camshaft
Plunger
	Fuel Temperature Sensor
	Q000393E
	-8-

B. Supply Pump Internal Fuel Flow

Fuel drawn from the fuel tank passes through the route in the supply pump as illustrated, and is fed into the rail.

Supply Pump Interior

Regulating Valve

Feed Pump

SCV (Suction Control Valve)

Discharge Valve

Rail

Overflow

Intake Valve

Pumping Portion (Plunger)

Fuel Tank

Q000394E

C.Construction of Supply Pump

•The eccentric cam is formed on the camshaft and is attached to the ring cam.

Ring Cam

Camshaft

Eccentric Cam

Q000395E

• As the camshaft rotates, the eccentric cam rotates eccentrically, and the ring cam moves up and down while rotating.

Eccentric Cam

Ring Cam

Camshaft

Q000396E

-9-

•The plunger and the suction valve are mounted on top of the ring cam. The feed pump is connected to the rear of the camshaft.

Plunger A

Ring Cam

Feed Pump

Plunger B

QD0728E

D. Supply Pump Operation

As shown in the illustration below, the rotation of the eccentric cam causes the ring cam to push Plunger A upwards. Due to the spring force, Plunger B is pulled in the opposite direction to Plunger A. As a result, Plunger B draws in fuel while Plunger A pumps it to the rail.

Suction Valve Delivery Valve

Plunger A

Eccentric Cam

Ring Cam

SCV

Plunger B

Plunger A: Finish Compression	Plunger A: Begin IntakePlunger
Plunger B: Finish Intake	B: Begin Compression

Plunger A: Begin Compression

Plunger A: Finish Intake

Plunger B: Begin Intake

Plunger B: Finish Compression

QD0707E

-10-

E. Description of Supply Pump Components

a.Feed Pump

The trochoid type feed pump integrated into the supply pump, draws fuel from the fuel tank and feeds it to the two plungers via the fuel filter and the SCV (Suction Control Valve). The feed pump is driven by the camshaft. With the rotation of the inner rotor, the feed pump draws fuel from its suction port and pumps it out through the discharge port. This is done in accordance with the space that increases and decreases with the movement of the outer and inner rotors.

Quantity Decrease

To Quantity Decrease (Fuel Discharge)

Pump Chamber

Outer Rotor

Inner Rotor

Intake Port

	Discharge	Quantity Increase	Quantity Increase
	Port
From			(Fuel Intake)
Fuel Tank			QD0708E

b.SCV (Suction Control Valve: Normally Open Type)

•A linear solenoid type valve has been adopted. The ECU controls the duty ratio (the duration in which current is applied to the SCV), in order to control the quantity of fuel that is supplied to the high-pressure plunger.

•The supply pump drive load decreases because intake fuel quantity is controlled to achieve the target rail pressure.

•When current flows to the SCV, the internal armature moves in accordance with the duty ratio. The fuel quantity is regulated by the cylinder, which moves in connection with the armature to block the fuel passage.

•With the SCV OFF, the return spring pushes the cylinder, completely opening the fuel passage and supplying fuel to the plungers. (Full quantity intake => full quantity discharge.)

•When the SCV is ON, the return spring contracts and closes the fuel passage.

•By turning the SCV ON/OFF, fuel is supplied in an amount corresponding to the drive duty ratio and then discharged by the plungers.

Return Spring

SCV

Cylinder

Pump Body

External View

Cross-Section

Q000050E

-11-