Land Rover Common Rail System Crs Denso Manual

Operation Section1–56
5.5 Other Injector Component Parts
(1) Hollow Screw with Damper
• The hollow screw with damper enhances injection quantity accuracy, by reducing the back-pressure pulsations (pres-
sure fluctuations) of the leak fuel. In addition, it minimizes the back-pressure dependence (the effect of the pressure
in the leak pipe changing the injection quantity even though the injection command is the same) of the fuel in the leak
pipe.
(2) Connector with Correction Resistor
• The connector with...

Operation Section1–57
(3) Injector with QR Codes
• QR (Quick Response) codes have been adopted to enhance correction precision. The QR code, which contains the
correction data of the injector, is written to the engine ECU. QR codes have resulted in a substantial increase in the
number of fuel injection quantity correction points, greatly improving injection quantity precision.
< NOTE >
QR codes are a new two-dimensional code that was developed by DENSO. In addition to injection quantity correction
data,...

Operation Section1–58
Handling Injectors with QR Codes (Reference) 
- Injectors with QR codes have the engine ECU recognize and correct the injectors, so when an injector or the engine
ECU is replaced, it is necessary to register the injectors ID code in the engine ECU.
Replacing the Injector
- It is necessary to register the ID code of the injector that has been replaced in the engine ECU. 
Replacing the Engine ECU
- It is necessary to register the ID codes of all the vehicle injectors in the engine...

Operation Section1–59
6.  DESCRIPTION OF CONTROL SYSTEM COMPONENTS
6.1 Engine Control System Diagram (Reference) 
Q000874E
Rail
Rail Pressure Sensor
Pressure Discharge Valve
Pressure Limiter
Injector Engine ECU
EDU
E-VRV for EGR
EGR Shut-Off VSV
Crankshaft Position Sensor 
(Engine Speed Sensor) Cylinder Recognition Sensor 
(TDC (G) Sensor:  HP2, 3, 4) Accelerator Position Sensor
Intake Air 
Temperature 
Sensor Airflow Meter 
(with Intake Air Temperature Sensor)
Coolant Temperature Sensor
Intake Air...

Operation Section1–60
6.2 Engine ECU (Electronic Control Unit)
zThe engine ECU constantly ascertains the status of the engine through signals from the sensors, calculates fuel injec-
tion quantities etc. appropriate to the conditions, actuates the actuators, and controls to keep the engine in an optimal
state. The injectors are actuated by either the EDU or the charge circuit in the engine ECU. This actuation circuit de-
pends on the specifications of the model it is mounted in. The ECU also has a...

Operation Section1–61
(2) Operation
• The high-voltage generating device in the EDU converts the battery voltage into high voltage. The ECU sends signals
to terminals B through E of the EDU in accordance with the signals from the sensors. Upon receiving these signals,
the EDU outputs signals to the injectors from terminals H through K. At this time, terminal F outputs the IJf injection
verification signal to the ECU.
6.4 Various Sensors
Various Sensor Functions
Sensor Functions
Crankshaft Position...

Operation Section1–62
(1) Crankshaft Position Sensor (Engine Speed Sensor) and Cylinder Recognition Sensor
{TDC (G) Sensor}
Crankshaft Position Sensor (Engine Speed Sensor)
• The crankshaft position sensor is installed near the crankshaft timing gear or the flywheel. The sensor unit is a MPU
(magnetic pickup) type. When the engine speed pulsar gear installed on the crankshaft passes the sensor section,
the magnetic field of the coil within the sensor changes, generating AC voltage. This AC voltage is...

Operation Section1–63
(2) Accelerator Position Sensor
• The accelerator position sensor converts the accelerator opening into an electric signal and outputs it to the engine
ECU. There are two types of accelerator position sensor: the hall element type and the contact type. In addition, to
provide backup in the event of breakdown, there are two systems and the output voltage is offset.
Hall Element Type
- This sensor uses a hall element to generate voltage from change in the direction of the magnetic...

Operation Section1–64
(3) Intake Air Temperature Sensor
• The intake air temperature sensor detects the temperature of the intake air after it has passed the turbocharger. The
sensor portion that detects the temperature contains a thermistor. The thermistor, which has an electrical resistance
that changes with temperature, is used to detect the intake air temperature.
(4) Mass Airflow Meter (with Built-In Intake Air Temperature Sensor)
• The mass air flow meter is installed behind the air cleaner and...

Operation Section1–65
(6) Fuel Temperature Sensor
• This is a thermistor type sensor that detects the fuel temperature. In the HP2, HP3, and HP4 systems, this sensor is
installed on the supply pump unit, but in the HP0 system, it is installed on a leak pipe from an injector.
(7) Intake Air Temperature Sensor and Atmospheric Pressure Sensor
• This sensor is a semiconductor type sensor. It measures pressure utilizing the piezoelectric effect that when the pres-
sure on the silicon element in the sensor...