C1256

DTC C1255 or C1256





Circuit Description
This DTC identifies a malfunction within the EBCM.

Conditions for Running the DTC
The ABS conditions and the braking conditions are normal.

Conditions for Setting the DTC
An internal EBCM malfunction exists.

Action Taken When the DTC Sets
C1255
If equipped, the following actions occur:
^ The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
^ The ABS indicator turns ON.
^ The Traction Control indicator turns ON.
^ The red Brake warning indicator turns ON.
^ The DIC displays the Service Stability System message.
^ For some DTC C1255xx, the EBCM disables the Variable Effort Steering (VES) for the duration of the ignition cycle and the DIC displays the Service Steering System message.

C1256
^ The ABS remains functional.
^ The ABS indicator remains OFF.

Conditions for Clearing the DTC
^ The condition for the DTC is no longer present (the DTC is not current) and you used the scan tool Clear DTC function.
^ The condition for the DTC is no longer present (the DTC is not current) and you used the On-Board Diagnostics Clear DTC function.
^ The EBCM automatically clears the history DTC when a current DTC is not detected in 50 consecutive drive cycles.

Diagnostic Aids
^ The scan tool displays 2 additional characters after the DTC. Take note of the 2 character code and any other DTCs that are set. The 2 character code is an engineering aid used in order to determine the cause of the internal malfunction.
^ A DTC C1255e2 can be caused by a battery or module disconnect. Inspect for a recent battery disconnect or module connector disconnect before replacing the EBCM.
^ A DTC C1255m5 can be set along with any wheel speed sensor DTC. Diagnose any wheel speed sensor DTCs before replacing the EBCM.
^ Make sure integrity of the connection between the EBCM and BPMV is secure, tight, and free from corrosion.

Test Description
The number below refers to the step number on the diagnostic table.
2. Determines whether the DTC is current.