Cooling fan system operation (at idle)
Courtesy of MAZDA MOTORS CORP.
- Connect WDS or equivalent to DLC-2.
- Verify that DTC P0480, P0481, and P0482 are not displayed.
- If DTC P0480, P0481 or P0482 are displayed, perform DTC inspection.
- Verify that ECT PID is below cooling fan operating temperature.
- Verify that the A/C switch and fan switch are off.
- Start the engine and idle it.
- Verify that the cooling fans are not operating.
- If cooling fan No. 1 is operating, inspect whether cooling fan relay No.2 is stuck in the closed position.
- If the cooling fans are operating, inspect whether cooling fan relay No.1 is stuck in the closed position.
- If the cooling fans are operating at high speed, inspect DTC for ECT sensor (P0117, P0118).
- If cooling fan No. 1 does not operate and cooling fan No.2 is operating, inspect whether cooling fan relay No.3 is stuck in the closed.
- Start the engine.
- Verify that the cooling fans are low speed when ECT PID is 100°C {212°F} or above
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- If cooling fan No. 1 does not operate, verify that DTC P0480 is not detected.
- If DTC P0480 is detected, perform DTC inspection.
- If DTC P0480 is not detected, inspect for the following:
- Cooling fan relay No.2 is stuck in open position.
- Open circuit in wiring harnesses or connectors or both between cooling fan relay No.2 and cooling fan motor No.1.
- If the cooling fan No.2 does not operate, verify that DTC P0482 is not detected.
- If DTC P0482 is detected, perform DTC inspection.
- If DTC P0482 is not detected, inspect the following:
- Cooling fan relay No.3 is stuck in open position.
- Open circuit in wiring harnesses or connectors or both between cooling fan relay No.3 and cooling fan motor No.2
- If cooling fan No. 1 or cooling fan No.2 or both are operating at high speed, verify that DTC P0481 is not detected.
- If DTC P0481 is detected, perform DTC inspection.
- If DTC P0481 is not detected, inspect the following:
- Cooling fan relay No.1 is stuck in closed position.
- Cooling fan relay No.4 is stuck in closed position.
- Turn A/C switch and fan switch on.
- Verify that A/C is operating.
- If A/C is not operating, inspect the following:
- A/C switch
- Fan switch
- Refrigerant pressure switch
- Verify that cooling fan No. 1 is operating at high speed and cooling fan No.2 is operating other than at low speed (high or middle speed).
- If the cooling fan relay does not operate high speed and cooling fan No.2 is operating low speed, inspect the following:
- Cooling fan relay No. 1 is stuck in open position.
- Cooling fan relay No.4 is stuck in open position.