| DETECTED CONDITION | POSSIBLE CAUSE |
| Cooling fan relay signal is not input to ECM. | Cooling fan relay circuit open or short ECM malfunction |
Inspection
Step 1
- 1) Turn the ignition switch OFF.
- 2) Remove the right frame side cover. (9-5)
- 3) Check the cooling fan relay coupler for loose or poor contacts.
If OK, then inspection the cooling fan relay. (8-8)
Is the cooling fan relay OK?
| YES | O/B and O/R wire open or shorted to ground, or poor 43 connection If wire and connection are OK, intermittent trouble or faulty ECM. Recheck each terminal and wire harness for open circuit and poor connection. Replace the ECM with a known good one, and inspect it again. |
| NO | Replace the cooling fan relay with a new one. |
- 4) After repairing the trouble, clear the DTC using SDS tool. (5-26)
Active control inspection
- 1) Set up the SDS tool. (Refer to the SDS operation manual for further details.)
- 2) Start the engine and run it idling condition.
- 3) Click "Cooling fan relay control" 1.
- 4) Click the operate button 2.
At this time, if an operation sound is heard from the cooling fan relay and cooling fan motor is operated, the function is normal.
Note: Cooling fan relay and cooling fan motor operation can be checked until the engine coolant temperature is less than 100°C (212°F) after starting the engine.
- 5) Click the stop button 3 to check the operation properly.
- 6) Click the off button 4 to check the cooling fan relay and cooling fan motor operation.
Note: This inspection should be begun from when the engine coolant temperature is below 50°C (122°F).
Check that the cooling fan relay operates for a few seconds as the engine coolant temperature arrives each at 50°C (122°F), 70°C (158°F) and 90°C (194°F) / above 4 000 r/min. It is cooling fan motor malfunction or its circuit failure when the motor would not run even if the relay turns to ON.
Note: There is a tolerance of operating temperature of cooling fan relay.
