Coolant Heater A Control Circuit Performance
The control circuit of coolant heater A reports a control circuit performance condition. Auxiliary preheating of the coolant cannot be commanded as expected.
Affected components
- Coolant heater a
- Wiring harness
- Ecm
Common causes
- High likelihood: Heater element aged - low output
- Medium likelihood: Supply voltage low under load
Diagnostic notes
- The malfunction indicator lamp may illuminate
Related codes
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.