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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information

IMM-312 Communication with the engine control module (ECM)

Condition




The diagnostic trouble code (DTC) applies only to cars with the EMS 2000 and Melco 1 or Melco 2 engine management systems.
In the two seconds after the ignition is switched on the immobilizer control module checks for too low a signal in the communication link between the immobilizer and engine control module. Diagnostic trouble code (DTC) IMM-312 is stored if a fault is found.

Possible source
- Short-circuit to ground in the communication link between immobilizer control module terminal #4 and the engine control module (ECM) when the engine is started.

Fault symptom[s]
- The indicator lamp on the combined instrument panel lights.

- The engine starts but stops immediately.