P1479
High Fan Control Primary Circuit Malfunction
Severity
⚠️ MediumCan you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–94 (est.)
Symptoms
- Engine overheating under high load conditions
- Cooling fan does not turn on at high speeds
- Check Engine Light Illuminated
- Reduced engine power when overheated
- Increase in coolant temperature
Causes
- Faulty fan relay
- Open or short circuit in control circuit
- Problems with wiring harness or contacts
- Faulty fan motor
- Problems with the engine control unit
How to Fix
- Check fuses associated with the cooling system
- Check the fan relay and replace if necessary
- Inspect the wiring harness and connectors for damage.
- Check the resistance and operation of the fan motor
- Check control signals from the ECU using a diagnostic scanner