Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information CEM-1A66

Condition




The central electronic module (CEM) checks the communication with the infotainment control module (ICM).
Diagnostic trouble codes (DTCs) are stored if the central electronic module (CEM) registers a fault in the communication with the infotainment control module (ICM).
The diagnostic trouble code (DTC) can be detected when the ignition is on for at least 10 seconds and the battery voltage is above > 10.5 volts.

Note! In the event of CEM-1A6x 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 infotainment control module (ICM)
- Open-circuit in the ground lead to the infotainment control module (ICM)
- Contact resistance in the terminals
- Open-circuit in the wiring for the CAN low speed network to the infotainment control module (ICM)
- The infotainment control module (ICM) 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]
- The audio system display does not function.