Radiator Main Fan Without AC
Radiator Main FanA: OPERATION (WITHOUT A/C MODEL)
DETECTING CONDITION:
- Engine coolant temperature is above 95°C (203° F).
TROUBLE SYMPTOM:
- Radiator main fan does not operate under the above condition.
1A1: CHECK POWER SUPPLY TO MAIN FAN MOTOR.
CAUTION: Be careful not to overheat engine during repair.
1) Turn ignition switch to OFF.
2) Disconnect connector from main fan motor.
3) Start the engine, and warm it up until engine coolant temperature increases over 95°C (203°F).
4) Stop the engine and turn ignition switch to ON.
5) Measure voltage between main fan motor connector and chassis ground.
Connector & terminal
(F17) No.2 (+) Chassis ground (-):
(CHECK) Is voltage more than 10 V?
(YES) Go to step 1A2.
(NO) Go to step 1A6.
1A2: CHECK POWER SUPPLY TO MAIN FAN MOTOR.
Measure voltage between main fan motor connector and chassis ground.
Connector & terminal
(F17) No.3 (+) Chassis ground (-):
(CHECK) Is voltage more than 10 V?
(YES) Go to step 1A3.
(NO) Go to step 1A6.
A3: CHECK GROUND CIRCUIT OF MAIN FAN MOTOR.
1) Turn ignition switch to OFF.
2) Measure resistance between main fan motor connector and chassis ground.
Connector & terminal
(F17) No.1 - Chassis ground:
(CHECK) Is resistance less than 5 ohms?
(YES) Go to step 1A4.
(NO) Repair open circuit in harness between main fan motor connector and chassis ground.
1A4: CHECK POOR CONTACT.
Check poor contact in main fan motor connector.
(CHECK) Is there poor contact in main fan motor connector?
(YES) Repair poor contact in main fan motor connector.
(NO) Go to step 1A5.
1A5: CHECK MAIN FAN MOTOR.
Connect battery positive (+) terminal to terminals No.2 and No.3, and negative (-) terminal to terminal No.1 of main fan motor connector.
(CHECK) Does the main fan rotate?
(YES) Repair poor contact in main fan motor connector.
(NO) Replace main fan motor with a new one.
1A6: CHECK FUSE.
1) Turn ignition switch to OFF.
2) Remove fuse No.13 from fuse and relay box.
3) Check condition of fuse.
(CHECK) Is the fuse blown-out?
(YES) Replace fuse.
(NO) Go to step 1A7.
1A7: CHECK A/C RELAY HOLDER.
3) Turn ignition switch to OFF.
2) Disconnect connectors from A/C relay holder.
3) Measure resistance between A/C relay holder connectors.
Connector & terminal
(F28) No.4 - (F29) No.2:
(CHECK) Is the resistance less than 1 ohm?
(YES) Go to step 1A8.
(NO) Repair open circuit in A/C relay holder short harness.
1A8: CHECK NC RELAY HOLDER.
Measure resistance between A/C relay holder connectors.
Connector & terminal (F30) No.4 - (F29) No.2:
(CHECK) Is the resistance less than 1 ohm?
(YES) Go to step 1A9.
(NO) Repair open circuit in A/C relay holder short harness.
1A9: CHECK MAIN FAN RELAY.
1) Turn ignition switch to OFF.
2) Remove main fan relay from fuse and relay box.
3) Check continuity between main fan relay terminals.
(CHECK) Does no continuity exist between terminals No.2 and No.4?
(YES) Go to step 1Ab.
(NO) Replace main fan relay.
1A1O: CHECK MAIN FAN RELAY.
1) Connect battery positive (+) terminal to terminal No.1 of main fan relay, and negative (-) terminal to terminal No.3.
2) Check continuity between main fan relay terminals.
(CHECK) Does continuity exist between terminals No.2 and No.4?
(YES) Go to step 1A11.
(NO) Replace main fan relay.
1A11: CHECK HARNESS CONNECTOR BETWEEN FUSE AND RELAY BOX AND NC RELAY HOLDER.
1) Turn ignition switch to OFF.
2) Disconnect connector from fuse and relay box.
3) Measure resistance of harness connector between fuse and relay box and A/C relay holder.
Connector & terminal (F40) No.3 - (F29) No.2:
(CHECK) Is resistance less than 1 ohm?
(YES) Go to step 1A12.
(NO) Repair open circuit in harness between fuse and relay box and A/C relay holder connector.
1A12: CHECK POOR CONTACT.
Check poor contact in fuse and relay box connector.
(CHECK) Is there poor contact in fuse and relay box connector?
(YES) Repair poor contact in fuse and relay box connector.
(NO) Go to step 1A13.
1A13: CHECK POOR CONTACT.
Check poor contact in A/C relay holder connector.
(CHECK) Is there poor contact in A/C relay holder connector?
(YES) Repair poor contact in A/C relay holder connector.
(NO) Go to step 1A14.
1A14: CHECK HARNESS CONNECTOR BETWEEN A/C RELAY HOLDER AND MAIN FAN MOTOR.
Measure resistance of harness connector between A/C relay holder and main fan motor.
Connector & terminal (F28) No.4 - (F17) No.2:
(CHECK Is resistance less than 1 ohm?
(YES) Go to step 1A15.
(NO) Repair open circuit in harness between A/C relay holder and main fan motor connector.
1A15: CHECK HARNESS CONNECTOR BETWEEN A/C RELAY HOLDER AND MAIN FAN MOTOR.
Measure resistance of harness connector between A/C relay holder and main fan motor.
Connector & terminal (F30) No.4- (F17) No.3:
(CHECK) Is resistance less than 1 ohm?
(YES) Go to step 1A16.
(NO) Repair open circuit in harness between A/C relay holder and main fan motor connector.
1A16: CHECK POOR CONTACT.
Check poor contact in A/C relay holder connector.
(CHECK) Is there poor contact in A/C relay holder connector?
(YES) Repair poor contact in A/C relay holder connector.
(NO) Go to step 1A17.
1A17CHECK POOR CONTACT.
Check poor contact in main fan motor connector.
(CHECK) Is there poor contact in main fan motor connector?
(YES) Repair poor contact in main fan motor connector.
(NO) Refer to "On-Board Diagnostics II System" diagnostics procedure.