Short-Circuit To Ground

Short-circuit to ground

IMM-312 Communication link to the engine control module (ECM)

Checking for a short-circuit
Check wiring for permanent short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and an intermittent short-circuit to ground according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.

Caution! The engine control module (ECM) must not be disconnected until at least 4 minutes after switching off the ignition. Neither may it be disconnected while the engine cooling fan (FC) is still running. (If nothing else is indicated when replacing the relevant engine control module (ECM)).

- Cars with Fenix 5.2, the cable between immobilizer control module #2 and engine control module (ECM) #B5.
- Cars with ME7, DENSO and MSA 15.8, the cable between the immobilizer control module #4 and engine control module (ECM) #B22.
- Cars with MSA 15.7, the cable between immobilizer control module #4 and engine control module (ECM) #B36.

Other information
- For information about the signals and other values, see Immobilizer signal specification Immobilizer Signal Specification.









Select Continue when the fault has been remedied.

Continue - Verification

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Verification




Verification

Hint: After finishing the repair check that the repair is successful and that the fault is corrected as follows.

- Ignition on.
- Erase diagnostic trouble codes (DTCs).
Start the engine a number of times.





Continue - Verification (continued)

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Verification (continued)




- Switch off the ignition for at least 3 seconds.
- Ignition on.
Read off diagnostic trouble codes (DTCs).





Is the diagnostic trouble code (DTC) still stored?

Yes - VERIFICATION FAILED

No - VERIFIED

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking for a short-circuit

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