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 34: ECU Hardware Performance RAM FailureDTC C056D 35: ECU Hardware Performance ROM Failure
DTC C056D 36: ECU Hardware Performance EEPROM Failure
DTC C056D 37: ECU Hardware Performance watchdog/safety uC Failure
DTC C056D 39: ECU Hardware Performance Internal Electronic Failure
DTC C056D 3C: ECU Hardware Performance Internal Communications Failure
Circuit/System Description
The electric parking brake control module has an internal motor, apply actuator, release actuator, and temperature sensor. The electric parking brake control module also contains the logic for applying and releasing the parking brake when commanded by the electric parking brake switch. When the electric parking brake control module receives a signal from the switch the internal circuit board temperature is checked to verify it is within operating range before the control module performs the requested operation.
Conditions for Running the DTC
Ignition OFF, ACCESSORY, or RUN mode.
Conditions for Setting the DTC
The electric parking brake control module detects an internal hardware malfunction.
Action Taken When the DTC Sets
| • | The electric parking brake is disabled. |
| • | A DIC message and/or a warning indicator may be displayed. |
Conditions for Clearing the DTC
| • | The electric parking brake control module clears the history DTC when a current DTC is not detected in 40 ignition cycles. |
| • | The condition for the DTC is no longer present. |
| • | The latest software and calibrations are programmed into the electric parking brake control module. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
Electronic Parking Brake Control Module Description
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Verification
- Verify DTC C056D 36 is not set.
- Remove the EPB fuse and reinstall. Verify DTC C056D is not set.
| ⇒ | If DTC is set, perform the Electronic Parking Brake Control Module Programming and Setup. |
| ⇒ | If DTC is set, replace the electric parking brake control module. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for electric parking brake control module replacement, setup, and programming.
