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Diagnostic Trouble Code (DTC) Information







Diagnostic trouble code (DTC) information

Condition
Central electronic module (CEM) sends, via the CAN-network, information about how long time has elapsed since the engine was turned off the last time. Engine control module (ECM) receives the signal and compares it to its own calculated time (calculated from temperature changes of engine temperature and inlet temperature).
If engine control module (ECM) detects that the received time differs too much from the calculated time, the diagnostic trouble code is generated.
The diagnostic trouble code can be diagnosed when the ignition is on.

Substitute value
- The calculated time is used.

Possible source
- Malfunction detected by another diagnostic function (engine temperature sensor, air pressure sensor inlet) in engine control module (ECM).
- Malfunction detected by central electronic module (CEM).
- Open-circuit in the control area network (CAN) wiring.
- Short-circuit between the control area network (CAN) wiring.
- Internal malfunction in central electronic module (CEM).
- Internal fault in the engine control module (ECM).
- Internal fault in another control module in the same part of the control area network (CAN).

Fault symptom[s]
- Nothing.