Circuit Description
This DTC identifies a malfunction within the electronic brake control module (EBCM).
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC C1255 Loss of Class 2 Communication |
| • | DTC C1256 EBCM/EBTCM Internal Malfunction |
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
| • | The EBCM disables the ABS for the duration of the ignition cycle. |
| • | The ABS indicator turns ON. |
| • | For some DTC C1255xx, the EBCM disables the DRP for the duration of the ignition cycle. |
| • | When the EBCM disables the DRP, the red Brake warning indicator turns ON. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
| • | The electronic brake control module (EBCM) automatically clears the history DTC when a current DTC is not detected in 100 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.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Does the DTC reset as a current DTC? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | |
3 | Replace the electronic brake control module (EBCM). Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming . Did you complete the repair? | Go to Step 4 | -- |
4 |
Does the DTC reset? | Go to Step 2 | System OK |
