Mitsubishi Electric Lancer Evolution-VII Workshop Manual page 1124

Inspection Procedure 2
Radiator fan does not change speed or stop.
Radiator fan controller uses the signal from engine-ECU to control radiator fan
motor in a continously variable mode.
Radiator fan relay continuity check (Refer to P.14-8.)
D Check the harness wire between radiator fan relay and
engine control relay.
D Check the harness wire between radiator fan relay and
body earth.
D Check the harness wire between radiator fan relay and
radiator fan controller.
Measure at the engine-ECU connector C-126.
<Vehicles without A/C>
D Connect the connector.
D Voltage between terminal 21 and body earth
(Engine: Idling, engine coolant temperature: 80_C or less)
OK: 0 - 0.3 V
(Engine: Idling, engine coolant temperature: 95_C or more)
OK: 0.7 V or more
<Vehicles with A/C>
D Connect the connector.
D Voltage between terminal 21 and body earth
(Engine: Idling, engine coolant temperature: 80_C or less)
OK: 0 - 0.3 V
(Engine: Idling, A/C switch: ON)
OK: 0.7 V or more (When A/C compressor is operating)
Radiator fan controller check (Refer to P.14-8.)
Measure at the engine-ECU connector C-126.
D Connect the connector.
D Pull out the teminal No.21 to disconnect it
(Ignition switch: ON)
OK: Radiator fan motor is rotated.
D Connect the teminal No.21 to the body earth
(Ignition switch: ON)
OK: Radiator fan motor stop running.
Engine-ECU terminal voltage check
(Refer to GROUP 13A - Troubleshooting.)
ENGINE COOLING -
OK
OK
OK
OK
YES
Troubleshooting
Probable cause
D Malfunction of radiator fan relay
D Malfunction of radiator fan controller
D Malfunction of engine-ECU
D Malfunction of harness, connector
NG
Replace
NG
Repair
Check the following connectors:
NG
<L.H. drive vehicles> C-126, A-13, A-21
<R.H. drive vehicles> C-126, C-136, A-21
OK
Check the trouble symptoms.
NG
Check the harness wire between radiator fan controller and
engine-ECU.
OK
Engine-ECU terminal voltage check
(Refer to GROUP 13A - Troubleshooting.)
NG
Replace the radiator fan controller.
NO
Replace the radiator fan controller.
14-5
NG
Repair
NG
Repair