For 1990-2009 cars only
Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provide an overview of each diagnostic category. |
DTC Descriptors
DTC C056D 00: ECU Hardware PerformanceDTC C120C: ECU Hardware Performance
DTC C121C: ECU Hardware Performance
DTC C121E: ECU Hardware Performance
DTC C123A: ECU Hardware Performance
DTC C123B: ECU Hardware Performance
DTC C123C: ECU Hardware Performance
DTC C123D: ECU Hardware Performance
DTC C123E: ECU Hardware Performance
DTC C123F: ECU Hardware Performance
DTC C1255: ECU Hardware Performance
DTC C1256: ECU Hardware Performance
DTC C126E: ECU Hardware Performance
DTC C127A: ECU Hardware Performance
DTC C127B: ECU Hardware Performance
DTC C127C: ECU Hardware Performance
DTC C12A7: ECU Hardware Performance
DTC C12C2: ECU Hardware Performance
DTC C12C5: ECU Hardware Performance
DTC C12C6: ECU Hardware Performance
DTC C12C8: ECU Hardware Performance
DTC C12CC: ECU Hardware Performance
DTC C12CF: ECU Hardware Performance
DTC C12D0: ECU Hardware Performance
DTC C12D1: ECU Hardware Performance
DTC C12D2: ECU Hardware Performance
DTC C12D3: ECU Hardware Performance
DTC C12D4: ECU Hardware Performance
DTC C12D5: : ECU Hardware Performance
DTC C12D6: : ECU Hardware Performance
DTC C12D7: : ECU Hardware Performance
DTC C12D8: : ECU Hardware Performance
DTC C12D9: : ECU Hardware Performance
DTC C12DA: : ECU Hardware Performance
DTC C12DB: : ECU Hardware Performance
DTC C12DC: : ECU Hardware Performance
DTC C12DD: : ECU Hardware Performance
DTC C12DE: : ECU Hardware Performance
DTC C12DF: : ECU Hardware Performance
DTC C12E0: : ECU Hardware Performance
DTC C12F2: : ECU Hardware Performance
DTC C12F3: : ECU Hardware Performance
DTC C12F4: : ECU Hardware Performance
DTC C12F5: : ECU Hardware Performance
DTC C12F6: : ECU Hardware Performance
DTC C12FE: : ECU Hardware Performance
DTC C056D 3C: ECU Hardware Performance Internal Communication Failure
DTC C056D 59: ECU Hardware Performance Circuit/Component Protection Time-out
DTC C12E9: ECU Hardware Performance Circuit/Component Protection Time-out
Circuit/System Description
The electronic brake control module (EBCM) detects an internal malfunction.
Conditions for Running the DTC
| • | Ignition ON. |
| • | Ignition voltage is greater than 10 volts. |
Conditions for Setting the DTC
The EBCM detects an internal malfunction.
Action Taken When the DTC Sets
| • | The EBCM disables the antilock brake system (ABS), traction control and the vehicle stability enhancement system (VSES) for the duration of the ignition cycle. |
| • | A DIC message and/or a warning indicator may be displayed. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
Verify DTC C056D is not set.
| ⇒ | If DTC is set, replace the EBCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for ABS replacement, setup, and programming
