Fan 4 Control Circuit High
The control circuit of cooling fan 4 reports a control circuit high condition. Fan operation cannot be commanded reliably.
Affected components
- Cooling fan 4
- Fan relay 4
- Ecm
Common causes
- High likelihood: Control wire shorted to B+
- Medium likelihood: Relay coil open
- Low likelihood: Connector pins corroded - high contact resistance
Diagnostic notes
- The malfunction indicator lamp may illuminate
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.