
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 timing
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 informa-
tion 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 injec-
tion 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 temperature.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
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 P5×PUMP C/MODULEZD30DDTi
EC-194
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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 timing
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 informa-
tion 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 injec-
tion 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 temperature.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
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 P7×F/INJ TIMG FBZD30DDTi
EC-197
http://vnx.su/

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 timing
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 informa-
tion 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 injec-
tion 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 temperature.
CAM RING POSITION SENSOR
The sensor detects the passing of the protrusion on the sensor
wheel in the injection pump by the semiconductor magnetic resis-
tance element sensor. The cam ring position sensor synchronizes
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 SYSTEM1ZD30DDTi
EC-237
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System Chart
Crankshaft position sensor
(TDC)E
ECM
Control sleeve position sensorE
Fuel temperature sensorE
Mass air flow sensorE
Engine coolant temperature sen-
sorE
Needle lift sensorE
Accelerator position sensorE
Accelerator position switchE
Air conditioner switchE
Ignition switchE
Battery voltageE
Vehicle speed sensorE
Brake switchE
Atmospheric pressure sensor
(inside ECM)E
EFuel injection controlEElectric governor
EFuel injection timing controlEInjection timing control valve
EFuel cut controlEFuel cut solenoid valve
EGlow control systemEGlow relay & glow lamp
EOn board diagnostic systemEMalfunction indicator
(On the instrument panel)
EEGR valve & Throttle control
valve controlEEGRC-solenoid valve A, B and
throttle control solenoid valve
(models for Germany)
EAir conditioning cut controlEAir conditioner relay
ENGINE AND EMISSION CONTROL OVERALL SYSTEMTD27Ti
EC-328
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FUEL TEMPERATURE COMPENSATION
Input/output signal line
Fuel temperature sensorEFuel temperatureECM
EElectric
governorCrankshaft position sensor (TDC)EEngine speed
Control sleeve position sensor
EControl sleeve position
The amount of fuel leaking at or around high-pressure parts inside the fuel injection pump varies with the fuel
temperature and engine speed. This will result in a difference between the target amount of fuel injected and
the actual amount. The ECM compensates for the actual amount depending on the signal obtained from the
fuel temperature sensor.
DECELERATION CONTROL
Input/output signal line
Accelerator position sensorEAccelerator position ECM
EElectric
governor
Crankshaft position sensor (TDC)EEngine speed
The ECM cuts power supply delivery to the electric governor during deceleration for better fuel efficiency. The
ECM determines the time of deceleration according to signals from the accelerator position sensor and crank-
shaft position sensor (TDC).
ENGINE AND EMISSION BASIC CONTROLSYSTEM DESCRIPTIONTD27Ti
Fuel Injection System (Cont'd)
EC-331
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Fuel Injection Timing System
SYSTEM DESCRIPTION
The fuel injection timing system determines the optimal fuel injection timing, based on engine speed, injection
quantity, engine coolant temperature and atmospheric pressure. The timing is formed by a basic value (Basic
Control) and two correction values. By performing a duty cycle signal on the timing control valve, the ECM
allows the valve to provide optimal injection timing. The ECM also performs feedback control on the timing
control valve using the signal from the needle lift sensor which detects the actual fuel injection timing.
BASIC CONTROL
Input/output signal line
Crankshaft position sensor (TDC)EEngine speedECM
E
Injection
timing con-
trol valve
Needle lift sensorEInjection timing
Control sleeve position sensor
EControl sleeve position
The optimal fuel injection timing data, predetermined in proportion
to engine speeds and amount of fuel injected, are stored in the
ECM memory. The ECM uses the data to control the fuel injection
timing.
HIGH ALTITUDE COMPENSATION
Input/output signal line
Crankshaft position sensorEEngine speed
ECM
E
Injection
timing
control
deviceControl sleeve position sensorEControl sleeve position
Atmospheric pressure sensor
EAtmospheric sensor
Needle lift sensor
EInjection timing
Fuel temperature sensor
EFuel temperatureEElectric
governor
For better drivability in high altitude areas, the fuel injection timing
is advanced and the fuel quantity is reduced according to the atmo-
spheric pressure.
SEF650S
ENGINE AND EMISSION BASIC CONTROL SYSTEM DESCRIPTIONTD27Ti
EC-332
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Test and Adjustment
WARNING:
When using nozzle tester, be careful not to allow diesel fuel
sprayed from nozzle to contact your hands or body, and make
sure your eyes are properly protected with goggles.
INJECTION PRESSURE TEST
1. Install nozzle to injection nozzle tester and bleed air from flarenut.
2. Pump the tester handle slowly (once per second) and watch the pressure gauge.
3. Read the pressure gauge when the injection pressure just starts dropping.Initial injection pressure: Used12,259 - 12,749 kPa (122.6 - 127.5 bar,
120 - 130 kg/cm
2, 1,706 - 1,849 psi)
New 12,749 - 13,730 kPa (127.5 - 137.3 bar,
130 - 140 kg/cm
2, 1,849 - 1,991 psi)
Always check initial injection pressure using a new nozzle.
4. To adjust injection pressure, change adjusting shims. (No. 2 - 4 nozzle)
a. Increasing the thickness of adjusting shims increases ini- tial injection pressure. Decreasing thickness reduces ini-
tial pressure.
b. A shim thickness of 0.04 mm (0.0016 in) corresponds approximately to a difference of 471 kPa (4.71 bar, 4.8
kg/cm
2, 68 psi) in initial injection pressure.
Refer to SDS for adjusting shim.
EF791A
SEF672A
SEF427F
INJECTION NOZZLETD27Ti
EC-339
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Symptom Matrix Chart
SYSTEM
Ð Basic engine
control systemSYMPTOM
Reference page
Feature of symptom, Check pointHARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER
POOR ACCELERATION
HI IDLE
LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEAT/HIGH ENGINE COOLANT TEMPERATURE
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION ABNORMAL SMOKE COLOR
DEAD BATTERY (UNDER CHARGE)
Malfunction indicator lamp illuminates.
Can be detected by CONSULT-II?
Fuel cut NO START (with first firing)
NO START (without first firing)
HARD TO START WHEN ENGINE IS COLD
HARD TO START WHEN ENGINE IS HOT
AT IDLE
DURING DRIVING
WHEN DECELERATING
BLACK SMOKE
WHITE SMOKENew CT/CS
AAAB AC AD AE AF AG AH AJ AK AL AM AP HA
Injec-
tion
timing Advanced
qq
IIqIqqIqEC-361
Retarded qq
IIqIqqIqEC-361
Electric injection
pump mainframe
IIIIqqqqqIqqqIIqqIq qqq Ð*1
Injection nozzle qqqqqqq
Iqq qIIIEC-336 *2
Glow system qq
III IEC-412
Engine body qq
IIqqqIqq qIIqqqIEM-
section *3
EGR system
II IEC-454
Air cleaner and
ducts
II IqMA-
section *4
I; High Possibility Item
q ; Low Possibility Item
*1: Insufficient or excess amount. Governor malfunction may be the cause.
*2: Depends on open-valve pressure and spray pattern.
*3: Caused mainly by insufficient compression pressure.
*4: Symptom varies depending on off-position of air duct, etc.
TROUBLE DIAGNOSESTD27Ti
EC-363
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