
Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 0701 P1zCAM POS SENYD25DDTi
EC-3542

Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 0702 P2zTDC PULSE SIGYD25DDTi
EC-3549

Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 0703 P3zPUMP COMM LINEYD25DDTi
EC-3556

Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 0704 P4zSPILL/V CIRC, DTC 0706 P6zSPILL VALVEYD25DDTi
EC-3563

Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 0705 P5zPUMP C/MODULEYD25DDTi
EC-3570

Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 0707 P7zF/INJ TIMG FBYD25DDTi
EC-3573

Description
SYSTEM DESCRIPTION
Sensor Input Signal to ECM ECM Function Actuator
Electronic controlled fuel injection pump Fuel injection signal
EGR volume
controlEGR volume control valve Crankshaft position sensor (TDC) Engine speed
Vehicle speed sensor Vehicle speed
Engine coolant temperature sensor Engine coolant temperature
Ignition switch Start signal
Accelerator position sensor Accelerator position
Battery Battery voltage
Air conditioner switch Air conditioner operation
PNP switch Park/Neutral position signal
Barometric pressure sensor (Built into
ECM)Barometric pressure
This system controls flow rate of EGR led from exhaust manifold
to intake manifold. The opening of the EGR by-pass passage in
the EGR volume control valve changes to control the flow rate.
A built-in step motor moves the valve in steps corresponding to
the ECM output pulses. The opening of the valve varies for opti-
mum engine control. The optimum value stored in the ECM is
determined by considering various engine conditions.
The EGR volume control valve remains close under the follow-
ing conditions.
+Engine stopped
+Engine starting
+Low engine coolant temperature
+Excessively high engine coolant temperature
+High engine speed
+Wide open throttle
+Low battery voltage
+Low barometric pressure
SEF908Y
DTC 1003 EGR VOLUME CONT/VYD25DDTi
EC-3605

Description
SYSTEM DESCRIPTION
The ECM and the electronic control fuel injection pump control
unit (abbreviated as the injection pump control unit) perform the
real time communication (signal exchange).
The ECM transmits the signals of the target fuel injection
amount, target fuel injection timing, and engine speed, etc., and
receives the signals of the pump speed and fuel temperature,
etc. from the injection pump control unit.
By those signals, the injection pump controls the optimum fuel
injection amount and injection timing of the spill valve and tim-
ing control valve.
Injection pump control unit has an on board diagnostic system,
which detects malfunctions related to sensors or actuators built-
into electronic control fuel injection pump. These malfunction
information are transferred through the line (circuit) from injection
pump control unit to ECM.
FUEL INJECTION AMOUNT CONTROL
In accordance with the target fuel injection amount signal from
the ECM, the injection amount is controlled by controlling the spill
valve in the injection pump and by changing the needle opening
time.
FUEL INJECTION TIMING CONTROL
Based on the target fuel injection timing signal from the ECM, the
injection timing is controlled in accordance with the timer spring
by performing the duty control of the timing control valve in the
injection pump and by adjusting the pressure of the timer piston
high pressure chamber.
FUEL TEMPERATURE SENSOR
The sensor detects the fuel temperature in the injection pump
and calibrates the injection amount change by the fuel tempera-
ture.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic
resistance element sensor. The cam ring position sensor syn-
chronizes with the cam ring, and detects the actual advance
amount. The injection pump control unit measures the injection
pump revolution by the signal of the cam ring position sensor.
SEF437Y
DTC 1004 FUEL CUT SYSTEM1YD25DDTi
EC-3614