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Diagnostic Trouble Code (DTC) Information






Diagnostic trouble code (DTC) information ECM-U012987

Condition
The anti-lock brake system module monitors the speed on the driven wheels and compares it with the actual vehicle speed. If the Brake control module (BCM) detects that the vehicle speed is greater than the speed at the driven wheels, the vehicle is considered to be slipping on the surface. To prevent slippage, the Brake control module (BCM) requests more torque to the driven wheels. The request is sent to the Engine control module (ECM) via the CAN network.
The Engine control module (ECM) checks the actual circumstances and evaluates the received signals before any torque increases are carried out.
The diagnostic trouble code (DTC) is stored if the control module detects that:
- The signal with the request about extra wheel torque from the Brake control module (BCM) is missing.
The control module's test for the diagnostic trouble code (DTC) starts in the event of:
- Engine running for at least 3 seconds.

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
- Look for the cause of the fault in the brake control module (BCM).
- Open-circuit in one of the control area network (CAN) cables.
- Short-circuit between the control area network (CAN) wiring.
- Internal fault in another control module in the same part of the control area network (CAN).

Fault symptom[s]
- Text window and warning symbol/Text message