Mitsubishi MOTORS Space Runner 1999 Workshop Manual Supplement page 427

13A-68
INSPECTION PROCEDURE 29
Fuel pump (low pressure) system
The engine-ECU turns on the fuel pump relay while the engine is cranking or
running, and supplies power source to the fuel pump (low pressure).
MUT-II Actuator test
07 Fuel pump (Refer to P.13A-80.)
NG
Check the fuel pump relay. (Refer to
P.13A-105.)
OK
Measure at fuel pump relay connector
B-27.
Disconnect the connector, and
measure at the harness side.
Voltage between terminals 3, 4 and
earth
(Ignition switch: ON)
OK: System voltage
OK
Measure at engine-ECU connector
B-28.
Disconnect the connector, and
measure at the harness side.
Voltage between terminal 22 and
earth (Ignition switch: ON)
OK: System voltage
OK
Measure at engine-ECU connector
B-28.
Disconnect the connector, and
measure at the harness side.
Short circuit between terminal 22
and earth (Ignition switch: ON)
OK: The fuel pump operates (its
operation sound can
heard).
NG
Measure at fuel pump (low pressure)
connector D-13.
Disconnect the connector, and
measure at the harness side.
(1) Voltage between terminal 5 and
earth
(Ignition switch: ON)
OK: System voltage
(2) Continuity between 4 and earth
OK: Continuity
OK
Check the following connector:
D-13
OK
Check trouble symptom.
NG
Replace the fuel pump (low pressure).
GDI –
Troubleshooting
OK
Normal
NG
Replace
NG
Check the following connector:
B-18
Check trouble symptom.
NG
Check the following connector:
B-27
OK
Check trouble symptom.
OK
Check the following connector:
B-28
Check trouble symptom.
be
(1) NG
Check the following connectors:
B-18, B-27, D-15
Check trouble symptom.
(2) NG
Check the following connector:
D-15
OK
Check trouble symptom.
NG
Repair
Probable cause
Malfunction of the fuel pump relay
Malfunction of the fuel pump (low pressure)
Open circuit or short-circuited harness wire in the fuel
pump (low pressure) circuit, or poor connector contact
Malfunction of the engine-ECU
NG
OK
NG
NG
Repair
NG
NG
OK
NG
NG
OK
NG
NG
Repair
NG
Repair
Check the harness wire between the
fuel pump relay and ignition switch.
OK
NG
Repair
Check the ignition switch. (Refer to
GROUP 54 – Ignition Switch.)
Check the harness wire between the
fuel pump relay and engine-ECU, and
repair if necessary.
Repair
Replace the engine-ECU.
Repair
Check the harness wire between
the fuel pump relay and fuel pump
(low pressure), and repair
necessary.
Check the harness wire between
the fuel pump and fuel pump drive
connector, and repair if necessary.
Check the harness wire between the
fuel pump (low pressure) and earth,
and repair if necessary.
if