fuel pump MITSUBISHI TRITON 1997 User Guide

MPI ± Troubleshooting13A-53
INSPECTION PROCEDURE 42
Check the engine-ECU power supply and earth circuit.
OK
Check trouble symptom.
OK
Check the harness wire
between engine-ECU and
ignition switch connector.NG
Repair
OK
Check the ignition switch.
(Refer to GROUP 54 ± Ignition Switch and Immobilizer System.)
4. NG
Check the harness wire between engine-ECU and earth, and repair
if necessary.
5. NG
OK
Check the following
connectors.
C-49, C-50, C-51NG
Repair
OK
Check trouble symptom.
NG
Replace the engine-ECU.
Check the following connectors.
A-56X, C-19, C-81, C-87NG
Repair
OK
Check trouble symptom
NG
Check the harness wire between engine-ECU and battery, and
repair if necessary.
NG
Check the harness wire between the engine-ECU and control relay,
and repair if necessary.
OK
Check trouble symptom.
2, 3. NG
Check the following
connector. C-53NG
Repair
Measure the engine-ECU connectors, C-49, C-50, C-51.

Disconnect the connector and measure at the harness side
1. Voltage between 62 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 38 and earth
OK:System voltage
3. Voltage between 12, 25 and earth (Ignition switch: ON)
OK:System voltage (when the terminal 38 is earthed)
4. Continuity between 13, 26 and earth
OK:Continuity
5. Voltage between 60 and earth
OK:System voltage1. NGCheck the following
connector. C-88NG
Repair
INSPECTION PROCEDURE 43
Check fuel pump circuit.
Measure at the fuel pump connector F-17.

Disconnect the connector and measure at the harness side.

Continuity between 2 and earth
OK:ContinuityNGCheck the following connectors.
D-02, F-17NG
Repair
OK
Check trouble symptom
NG
Check the harness wire between fuel pump and earth, and repair
if necessary.
OK
Check the following connectors. C-19, D-02, F-17NG
Repair OKCheck trouble symptom.
NG
Check the harness wire between terminal for fuel pump drive and
fuel pump connector.NG
Repair
OK
Replace the fuel pump.

MPI ± Troubleshooting13A-54
INSPECTION PROCEDURE 44
Check the fuel pump drive control circuit.
Measure at the fuel pump relay connector C-54.

Disconnect the connector and measure at the harness side.

Voltage between 4 and earth (Ignition switch: ON)
OK:System voltageNGCheck the following
connector. C-88NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire
between fuel pump relay
and ignition switch con-
nector.NG
Repair
OK
Check the ignition switch.
(Refer to GROUP 54 ± Ignition Switch and Immobilizer System.)
OK
Measure at the engine-ECU connector C-49.

Disconnect the connector and measure at the harness side.


Voltage between 8 and earth (Ignition switch: ON)
OK:System voltage


Voltage between 22 and earth (Ignition switch: ON)
OK:System voltageNG
Check the following
connector. C-54NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire between engine-ECU and fuel pump relay
connector, and repair if necessary.
OK
Check the following connector. C-49NG
Repair
OK
Check trouble symptom.
NG
Replace the engine-ECU.
INSPECTION PROCEDURE 45
Check air flow sensor (AFS) control circuit.
Measure at the air flow sensor connector A-77.

Disconnect the connector and measure at the harness side.
1. Voltage between 4 and earth (Ignition switch: ON)
OK:System voltage
2. Voltage between 3 and earth (Ignition switch: ON)
OK:4.8 ± 5.2 V
3. Continuity between 5 and earth
OK:Continuity1. NGCheck the harness wire between the air flow sensor and control
relay connector, and repair if necessary.
2, 3. NGCheck the following
connector. C-51NG
Repair
OK
Check trouble symptom.
NG
Check the harness wire
between the engine-ECU
and air flow sensor con-
nector.NG
Repair
OK
Replace the engine-ECU.
OK
Check the following connector. A-77NG
Repair
OK
Check trouble symptom.
NG
Replace the air flow sensor.

MPI ± Troubleshooting13A-62
ACTUATOR TEST REFERENCE TABLE13100900210
Item
No.Inspection
itemDrive contentsInspection contentsNormal conditionInspection
procedure
No.Reference
page
01InjectorsCut fuel to No.1,
No.3 injectorEngine:
After having warmed up/En-
gine is idling
(Cut the fuel supply to each
Idling condition
becomes different
(becomes unsta-
ble)
Code No.
4113A-19
02Cut fuel to No.2,
No.4 injector(Cut the fuel supply to each
injector in turn and check
cylinders which don't affect
idling.)
ble).
07Fuel pumpFuel pump
operates and
fuel is recircu-
lated.
Engine:
Cranking

Fuel
pump:
Forced
driving
Inspect
accord-
Pinch the
return hose
with fingers
to feel the
pulse of the
fuel being
recirculated.Pulse is felt.Procedure
No. 2413A-40
accord-
ing to
both the
above
condi-
tions.
Listen near
the fuel tank
for the
sound of fuel
pump
operation.Sound of operation
is heard.
08Purge
control
solenoid
valveSolenoid valve
turns from OFF
to ON.Ignition switch: ONSound of operation
can be heard when
solenoid valve is
driven.Procedure
No. 3213A-45
10EGR
control
solenoid
valveSolenoid valve
turns from OFF
to ON.Ignition switch: ONSound of operation
can be heard when
solenoid valve is
driven.Procedure
No. 3313A-46

MPI ± On-vehicle Service13A-83
14. Stop the engine and check change of fuel pressure gauge
reading. Normal if the reading does not drop within 2
minutes. If it does, observe the rate of drop and
troubleshoot and repair according to the table below.
SymptomProbable causeRemedy
Fuel pressure drops gradually after
engine is stopped
Leaky injectorReplace injector
engine is sto ed
Leaky fuel regulator valve seatReplace fuel pressure regulator
Fuel pressure drops sharply
immediately after engine is stoppedCheck valve in fuel pump is held openReplace fuel pump
15. Release residual pressure from the fuel pipe line. (Refer
to P.13A-84.)
16. Remove the fuel pressure gauge and special tool from
the delivery pipe.
Caution
Cover the hose connection with rags to prevent splash
of fuel that could be caused by some residual pressure
in the fuel pipe line.
17. Replace the O-ring at the end of the fuel high pressure
hose with a new one. Furthermore, apply engine oil to
the new O-ring before replacement.
18. Fit the fuel high pressure hose over the delivery pipe
and tighten the bolt to specified torque.
Tightening torque: 5 Nm
19. Check for fuel leaks.
(1) Apply the battery voltage to the fuel pump drive
terminal to drive the fuel pump.
(2) Under fuel pressure, check the fuel line for leaks.

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-13
INSPECTION CHART FOR DIAGNOSIS CODES

54300710034
Diagnosis code No.Inspection itemsReference page
11Transponder communication system or radio interference of ID
code54-11
12*ID codes are not the same or not registered54-11
21Communication system between fuel cut valve controller and
immobilizer-ECU54-13
22Malfunction of fuel cut valve controller system54-14
23Identification codes are not identical54-14
31EEPROM abnormality inside immobilizer-ECU54-12
NOTE
*: diagnosis code No.12 is recorded.
INSPECTION PROCEDURE FOR DIAGNOSIS CODES

For diagnosis code numbers other than those listed below, refer to ªPETROL-POWERED VEHICLESº.
Code No.21 Communication system between fuel cut
valve controller and immobilizer-ECU
Probable cause
The confirmation code is not sent from the fuel cut valve controller within the specified
time after the ignition key is turned to ON or, an incorrect code is sent.
Malfunction of harness or connector

Malfunction of fuel cut valve controller

Malfunction of immobilizer-ECU
Check the following connectors: A-90, C-19, C-36NG
Repair
OK
Check trouble symptom.
NG
Check the harness between the immobilizer-ECU and fuel cut valve
controller.NG
Repair
OK
Check the fuel cut valve controller power source and earth circuit.
(Refer to P.54-17, Inspection Procedure 6.)NG
Repair
OK
Check trouble symptom.NGReplace the immobilizer-ECU.
Register the password (secret code), reset the code to the factory
setting and register the ID code. (Refer to P.54-23.)
Check trouble symptom.
NG
Replace the fuel cut valve controller (fuel injection pump assembly).

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-14
Code No.22 Malfunction of fuel cut valve controller
systemProbable cause
The cause is probably a malfunction of the fuel cut valve controller.
Malfunction of fuel cut valve controller
Check the fuel cut valve controller power source and earth circuit.
(Refer to P.54-17, Inspection Procedure 6.)
OK
Check trouble symptom.NGReplace the fuel cut valve controller (fuel injection pump assembly).
Code No.23 Identification codes are not identicalProbable cause
The identification code received from the immobilizer-ECU is not identical to the
identification code that has been recorded in the fuel cut valve controller.
Resetting the code to the factory setting is not made
using the MUT-II

Malfunction of fuel cut valve controller
Use the MUT-II to reset the code to the factory setting.
(Refer to P.54-23.)
Check trouble symptom.NGReplace the fuel cut valve controller (fuel injection pump assembly).
Check trouble symptom.
NG
Replace the immobilizer-ECU.
Register the password (secret code), reset the code to the factory
setting and register the ID code. (Refer to P.54-23.)
INSPECTION CHART FOR TROUBLE SYMPTOMS54300720242
Trouble symptomInspection procedure No.Reference page
Communication with MUT-II is impossible154-15
ID code cannot be registered using the MUT-II254-15
Engine does not start (Cranking but no initial combustion).
354-16
Engine does not start (Cranking but no initial combustion).
454-16
Malfunction of the immobilizer-ECU power source and
earth circuit554-17
Malfunction of the fuel cut valve controller power source
and earth circuit 654-17

CHASSIS ELECTRICAL ± Ignition Switch and Immobilizer System54-16
Inspection Procedure 3
Engine does not start (Cranking but no initial combus-
tion).
Probable cause
If the fuel injectors are not operating, there might be a problem with the MPI system
in addition to a malfunction of the immobilizer system.
It is normal for this to occur if an attempt is made to start the engine using a key
that has not been properly registered.
Malfunction of MPI system

Malfunction of immobilizer-ECU
Check the system voltage during crank-
ing
OK:8 V or moreNGCheck the battery.
OK
Is a diagnosis code displayed from the
immobilizer-ECU?Ye sTo INSPECTION CHART FOR DIAG-
NOSIS CODE. (Refer to P.54-10.)
No
Is a diagnosis code displayed from the
engine-ECU?Ye sRefer to GROUP 13A ± Troubleshoot-
ing.
No
Check the starting system. (Refer to
GROUP 13A ± Troubleshooting.)
OK
Check trouble symptom.
NG
Check the immobilizer-ECU power
source and the earth circuit. (Refer to
P.54-17, Inspection Procedure 5.)OKCheck trouble symptom.NGReplace the immobilizer-ECU.
Register the password (secret code)
and the ID code. (Refer to P.54-23.)
Inspection Procedure 4
Engine does not start (Cranking but no initial combus-
tion).
Probable cause
If no fuel injection, there might be a problem with the fuel injection system in addition
to a malfunction of the immobilizer system.
It is normal for this to occur if an attempt is made to start the engine using a key
that has not been properly registered.
Malfunction of diesel fuel injection system

Malfunction of immobilizer-ECU
Check the system voltage during crank-
ing
OK:8 V or moreNGCheck the battery.
OK
Is a diagnosis code displayed from the
immobilizer-ECU?Ye sTo INSPECTION CHART FOR DIAG-
NOSIS CODE. (Refer to P.54-13.)
No
Check the diesel fuel injection system.
(Refer to GROUP 13E ± On-vehicle Ser-
vice.)
OK
Check the immobilizer-ECU power sup-
ply and the earth circuit. (Refer to
P.54-17, Inspection Procedure 5.)OKCheck trouble symptom.NGReplace the immobilizer-ECU.
Register the password (secret code),
reset the code to the factory setting and
register the ID code. (Refer to P.54-23.)
Check trouble symptom.
NG
Replace the fuel cut valve controller
(fuel injection pump assembly).