Diagnostic Trouble Code (DTC) Information

Diagnostic trouble code (DTC) information ECM-U012900

Condition
Engine control module (ECM) and Brake control module (BCM) contain a code that is unique code for each vehicle for electronic immobilizer. In addition to this, each key for the vehicle is electronically coded for the intended vehicle only. Internal checks are made at the start to check that the key is the correct one for the vehicle and that the immobilizer codes in the Engine control module (ECM) and Central electronic module (CEM) correspond.
The diagnostic trouble code (DTC) is stored if the control module detects that:
- If Engine control module (ECM) registers that communication between Engine control module (ECM) and Brake control module (BCM) (via CAN) is missing.
The control module's test for the diagnostic trouble code (DTC) starts in the event of:
- Ignition on.

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.

Substitute value
- None.

Possible source
- Open circuit on one of the CAN-cables.
- Short-circuit between CAN-cables.
- Damaged engine control module (ECM).

Fault symptom[s]
- The engine does not start.
- Message in the display.