Fuel Pump System - Mitsubishi Electric Lancer Evolution-VII Workshop Manual

Inspection Procedure 23

Fuel pump system

D The engine-ECU turns the fuel pump relay ON during cranking and engine
operation, and supplies the drive power to the fuel pump.
D When operating with a low load, the engine-ECU supplies power to the fuel
pump via the resistor. When operating with a high load, power is directly
supplied and the fuel pump fuel discharge amount is increased.
MUT-II Actuator Test
No. 07: Fuel pump
(Refer to P.13A-107.)
NG
Check the fuel pump relay 1, fuel
pump relay 2 and fuel pump registor.
(Refer to P.13A-132.)
OK NG
Measure at the C-223 fuel pump
relay 1.
D Disconnect the connector to
measure at the harness side.
(1) Voltage between terminal No. 3
and earth
OK: System voltage
(2) Voltage between terminal No. 1
and earth
(Ignition switch: ON)
OK: Battery voltage
(2) Resistance between terminal No.
4 and earth
OK: 2 Ω or less
OK
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MPI -
OK
MUT-II Actuator Test
No. 13: Fuel pump relay 3
(Refer to P.13A-107.)
Check the fuel pump relay 3.
(Refer to P.13A-132.)
Repair
Measure at the B-140 fuel pump
relay 3.
D Disconnect the connector to
measure at the harness side.
D Voltage between terminal No. 2,
terminal No. 4 and earth
(Ignition switch: ON)
OK: System voltage
Measure at the C-122 engine-ECU
connector.
D Disconnect the connector to
measure at the harness side.
D Disconnect the C-126
engine-ECU connector, and earth
the terminal No. 22.
D Voltage between terminal No. 126
and earth
(Ignition switch: ON)
OK: System voltage
(1) NG
Check the following connectors:
C-209, C-135
OK
Check the trouble symptoms.
Check and repair the harness
between the fuel pump relay 1 and
battery.
(2) NG
Check the following connector:
C-210
Check the trouble symptoms.
(3) NG
Check the following connectors:
C-223, C-08 <R.H. drive vehicle>,
C-102 <L.H. drive vehicle>
OK
Check the trouble symptoms.
Check and repair the harness
between the fuel pump relay 1 and
body earth.
Troubleshooting
Probable cause
D Fuel pump relay 1 malfunction
D Fuel pump relay 2 malfunction
D Fuel pump relay 3 malfunction
D Fuel pump resistor malfunction
D Fuel pump malfunction
D Fuel pump circuit disconnection, short-circuit, or
connector contact defect
D Engine-ECU malfunction
OK
NG
NG
OK
NG
OK
OK
NG
NG
Repair
NG
NG
OK
NG
NG
Repair
NG
13A-85
Intermittent malfunction (Refer to
GROUP 00 - Points to Note for
Intermittent Malfunctions.)
Replace the fuel pump relay 3.
Check and repair the harness
between the fuel pump resistor and
fuel pump relay 3.
Check the following connector: C-122
NG
OK
Check the trouble symptoms.
NG
Check the harness between the fuel
pump relay 3 and fuel pump resistor.
OK NG
Replace the engine-ECU.
Check and repair the harness
between the fuel pump relay 3 and
engine-ECU.
Repair
Check the harness between the fuel
pump relay 1 and ignition switch.
NG
OK
Check the ignition switch. (Refer to
GROUP 54 - Ignition Switch.)
Repair
Repair
Repair