P0495: Cooling fan speed too high — what it means, the affected system and what to check before replacing parts.
Meaning, symptoms, causes and checks
The monitored fan speed is too high for the controller’s expectation. This is a speed condition, not the same as a low/high electrical control-circuit code. The feedback signal and fan command must be interpreted for the fitted fan system.
Affected system: Engine cooling fan control
Symptoms
- The cooling fan may run faster or louder than expected, including when the engine is not especially hot.
- An engine warning or abnormal air-conditioning behavior can accompany the fan-control fault.
Possible causes
- A fan relay, control circuit or electrical connection may keep the fan at excessive speed.
- Depending on the design, a faulty fan clutch or fan-control assembly may also cause the condition.
What to check
- Check related cooling-system codes and compare commanded fan speed with observed fan operation under the test conditions specified for the vehicle.
- Keep clear of the fan, which can start unexpectedly; inspect the relay, wiring and fitted fan-control mechanism before deciding which component is faulty.
Also written as: P0495-00, P049500, PO495 (some scan tools add the fault-type byte, e.g. -00).