Diagnostic trouble code (DTC) information CEM-5F4D
Condition
The central electronic module (CEM) checks the communication with the combustion preheater module (CPM).
The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers that the internal diagnostics in the combustion preheater module (CPM) do not respond within a certain time.
The diagnostic trouble code (DTC) can be diagnosed when the heater is activated.
Substitute Value
- None.
Possible Source
- Contact resistance in the terminals.
- Open-circuit in the communication cable.
- Short-circuit to ground in the communication cable.
- Short-circuit to supply voltage in the communication cable.
Fault symptom[s]
- Poor heating in the passenger compartment.
- Parking heater/Does not work