Diagnostic Trouble Code (DTC) Information CEM-De23

Condition 

The diagnostic trouble code (DTC) is stored if the central electronic module (CEM) registers that communication with the trailer module (TRM) is not operating.

The diagnostic trouble code (DTC) can be diagnosed when the ignition has been on for at least 10 seconds.

Substitute Value 

• None.

Possible Source 

• No power supply to the trailer module (TRM)
• Open-circuit in the ground lead to the trailer module (TRM)
• Contact resistance in the terminals
• Open-circuit in the wiring for the CAN low speed network to the trailer module (TRM)
• The trailer module (TRM) 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. 

Fault symptom[s] 

• Functions controlled by the trailer module (TRM) are lost.