Diagnostic Trouble Code (DTC) Information CEM-De1A
Condition
The diagnostic trouble code (DTC) is generated if the central electronic module (CEM) registers that communication with the Differential Electronic Module (DEM) is not operating.
In the event of CEM-DEXX diagnostic trouble codes (DTCs) being stored the central electronic module (CEM) must not be replaced; the diagnostic trouble code (DTC) indicates a communication fault in the Control area network
The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.
Substitute Value
- None.
Possible Source
- Voltage supply to the Differential electronic module (DEM) is missing.
- Open circuit in ground lead for the Differential electronic module (DEM).
- Contact resistance in the terminals.
- Open circuit in the wiring for the CAN low-speed network to the Differential Electronic Module (DEM)
- Differential Electronic Module (DEM) is not intended for this car, e. g., used control module with other hardware/software.
HINT: If several diagnostic trouble codes (DTCs) are stored in the central electronic module (CEM) for communication faults with other control modules in the low speed network, this indicates a common fault in the Control area network.
Fault symptom[s]
- 4-wheel/all wheel drive/Does not work
- Text window and warning symbol/Text message