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Diagnostic Trouble Code (DTC) Information







Diagnostic trouble code (DTC) information CEM-1A66

Condition




The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers that communication with the infotainment control module (ICM) is not operating.
The diagnostic trouble code (DTC) can be diagnosed when the ignition has been on for more than 10 seconds.

Note! If CEM-1A6X diagnostic trouble codes (DTCs) are stored, 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 for 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 vehicle, 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.
- Functions in the infotainment system do not work.