CEM-5F4F

Condition







If the control unit indicates that a start attempt has failed, diagnostic trouble code CEM-5F4F will be stored.

Substitute value

- The heater is not activated.

Possible source

- Leakage in the heater fuel system.
- Defective fuel pump.
- Blocked combustion air flow.
- No fuel feed.
- Contact resistance in control unit connector.
- Open circuit or short circuit to voltage supply on the control signal wire of the flame indicator.
- Flame indicator covered with soot.
- Defective flame indicator.

Fault symptom[s]

- Poor interior heating.