Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information CEM-1A5C

Condition




Diagnostic trouble codes (DTCs) are stored if the central electronic module (CEM) registers that communication with the upper electronic module (UEM) is not operating.

Note! In the event of CEM-1A5X diagnostic trouble codes (DTCs), the central electronic module (CEM) must not be replaced as the diagnostic trouble code (DTC) indicates a communication fault in the Control area network!

Substitute value
None.

Possible source
- No power supply to the upper electronic module (UEM)
- Open-circuit in the ground lead to the upper electronic module (UEM)
- Contact resistance in the terminals
- Open-circuit in the wiring for the CAN low speed network to the upper electronic module (UEM)
- The upper electronic module (UEM) is not intended for this car (for example a used control module with different software/hardware.

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, see the wiring diagram.

Fault symptom[s]
- Cannot be controlled with the remote control
- The power sun roof does not operate
- The interior lighting does not work.