Land Rover Common Rail System Crs Denso Manual

Operation Section1–6
1.7 Common Rail System Configuration
zThe common rail control system can be broadly divided into the following four areas: sensors, engine ECU, EDU, and
actuators.
Sensors
zDetect the condition of the engine and the pump.
Engine ECU
zReceives signals from the sensors, calculates the proper injection quantity and injection timing for optimal engine oper-
ation, and sends the appropriate signals to the actuators.
EDU
zEnables the injectors to be actuated at high speeds. There are also...

Operation Section1–7
2.  COMMON RAIL SYSTEM OUTLINE
2.1 Layout of Main Components
zCommon rail systems are mainly made up of the supply pump, rail, and injectors. There are the following types accord-
ing to the supply pump used.
(1) HP0 Type
• This system is the first common rail system that DENSO commercialized. It uses an HP0 type supply pump and is
mounted in large trucks and large buses.
Exterior View of Main System Components
Configuration of Main System Components (Example of HP0)
Q000755E...

Operation Section1–8
(2) HP2 Type
• This system uses a type of HP2 supply pump that has been made lighter and more compact, and is the common rail
system for passenger cars and RVs instead of the ECD-V3.
Exterior View of Main System Components
Mounting Diagram of Main System Components
Q000757E
InjectorSupply Pump (HP2 Type)
Rail
Engine ECU
EDU (Electronic Driving Unit) EGR Valve
E-VRV
Intake Air Temperature 
SensorIntake Air  Pressure  Sensor
Injector
Crankshaft Position Sensor 
(Engine Speed Sensor)...

Operation Section1–9
Overall System Flow (Fuel)
Q000926E
Supply Pump
Plunger Feed PumpDelivery Valve
SCV 
(Suction 
Control 
Va lve)
Inner Cam Regulating Valve
Check Valve
Rail
Rail Pressure Sensor
Pressure 
Limiter
InjectorTWV Engine 
ECUEDU
Various Sensors
Fuel Filter
Fuel Tank
: Flow of Injection Fuel
: Flow of Leak Fuel 

Operation Section1–10
(3) HP3 Type, HP4 Type
HP3 Type
• This system uses an HP3 type supply pump that is compact, lightweight and provides higher pressure.  It is mostly
mounted in passenger cars and small trucks.
HP4 Type
• This system is basically the same as the HP3 type, however it uses the HP4 type supply pump, which has an in-
creased pumping quantity to handle larger engines. This system is mostly mounted in medium-size trucks. 
Exterior View of Main System Components
Mounting Diagram for Main...

Operation Section1–11
Overall System Flow (Fuel)
Q000927E
Supply Pump 
(HP3 or HP4)
Plunger
Feed PumpDelivery 
Va l v e
SCV 
(Suction 
Control Valve)
Rail
Rail Pressure SensorPressure Discharge Valve
Pressure Limiter
Injector ECUEDU
Various 
Sensors
Fuel Filter
Fuel Tank
: Flow of Injection Fuel
: Flow of Leak Fuel 

Operation Section1–12
3. SUPPLY PUMP DESCRIPTION
3.1 HP0 Type
(1) Construction and Characteristics
• The HP0 supply pump is mainly made up of a pumping system as in conventional in-line pumps (two cylinders), the
PCV (Pump Control Valve) for controlling the fuel discharge quantity, the cylinder recognition sensor {TDC (G) sen-
sor}, and the feed pump.
• It supports the number of engine cylinders by changing the number of peaks on the cam. The supply pump rotates at
half the speed of the engine. The...

Operation Section1–13
(2) Exploded View
Q000769E
PCV 
(Pump Control Valve)
Delivery Valve
Element
Cylinder Recognition Sensor
(TDC (G) Sensor)
Roller Cam
CamshaftTappet
Feed Pump Priming Pump  

Operation Section1–14
(3) Supply Pump Component Part Functions
Feed Pump
• The feed pump, which is integrated in the supply pump, draws fuel from the fuel tank and feeds it to the pump chamber
via the fuel filter. There are two types of feed pumps, the trochoid type and the vane type.
Trochoid Type
- The camshaft actuates the outer/inner rotors of the feed pump, causing them to start rotating. In accordance with
the space produced by the movement of the outer/inner rotors, the feed pump draws fuel into...

Operation Section1–15
PCV: Pump Control Valve
• The PCV (Pump Control Valve) regulates the fuel discharge quantity from the supply pump in order to regulate the
rail pressure. The fuel quantity discharged from the supply pump to the rail is determined by the timing with which the
current is applied to the PCV.
Actuation Circuit
- The diagram below shows the actuation circuit of the PCV. The ignition switch turns the PCV relay ON and OFF to
apply current to the PCV. The ECU handles ON/OFF control of the...