Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information CEM-DD02

Condition




The central electronic module (CEM) sends and receives information via a standardized serial communication system. This system is called Volcano Lite (VOLvo CAN based distributed real time Operative environment). The diagnostic trouble code (DTC) is stored if the control module registers serious interference such as blocked communication with the light switch module (LSM) or combustion preheater module (CPM).
The diagnostic trouble code (DTC) can be diagnosed when the ignition key is in position II for at least 10 seconds and the battery voltage exceeds 10.5 V.
Note! In the event of CEM-DDxx diagnostic trouble codes (DTCs), the central electronic module (CEM) must not be replaced as the diagnostic trouble code (DTC) indicates a short-circuit in one or more conductors. The central electronic module (CEM) is the only control module that monitors the voltage level in the signal cables. The central electronic module (CEM) is therefore the only control module that can store a diagnostic trouble code (DTC) for a short-circuit in one of the cables to ground or supply voltage. Do not replace the central electronic module (CEM) in the event of this type of fault unless VIDA fault-tracing has indicated that the central electronic module (CEM) has an internal fault.

Substitute value
- None.

Possible source
- Short-circuit to ground in the signal cable
- Internal fault in another control module in the same part of the network.

Fault symptom[s]
- The light switch does not operate
- Beam height control does not function
- The parking heater does not operate.