Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information CEM-U023500

Condition
The control modules communicate with each other for exchange of information in a network via a standardized serial communication procedure - CAN (Controller Area Network).
The diagnostic trouble code (DTC) is stored if the control module detects that:
- Interrupted or missing communication with the Closing velocity module (CVM).
- Incorrect value lasts longer than 10 seconds.
The control module's test for the diagnostic trouble code (DTC) starts in the event of:
- Ignition switch position II. Engine running.

Note! The control module can only detect the fault once the test has been started and the diagnostic trouble code (DTC) is stored when the conditions are met. The diagnostic trouble code (DTC) indicates a fault in the communication across the CAN network and does not isolate an individual node. Do not replace the central electronic module (CEM) unless fault-tracing indicates a damaged control module.





Substitute value
- None.

Possible source
- Power supply to the Closing velocity module (CVM) missing.
- Open circuit on ground cable to the Closing velocity module (CVM).
- Contact resistance in the terminals.
- Open-circuit or short-circuit in the wiring for the control area network (CAN).
- The Closing velocity module (CVM) is not intended for this vehicle, for example used control module with other 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]
- Front monitoring/Active safety/City Safety does not work
- Front monitoring/Active safety/City Safety no activation