Antilock Brake System

DTC C0550

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 provides an overview of each diagnostic category.



DTC Descriptor
DTC C0550 00
- Electronic Control Unit (ECU) Performance


DTC C0550 02
- Electronic Control Unit (ECU) Performance short to ground


DTC C0550 04
- Electronic Control Unit (ECU) Performance open circuit




Circuit/System Description

The electronic brake control module (EBCM) detects an internal performance, short to ground, or open circuit malfunction exists.


Conditions for Running the MIL/DTC

The ignition switch is in the ON position.


Conditions for Setting the MIL/DTC

An internal EBCM malfunction exists. An internal open or short to ground circuit within the EBCM exists.


Action Taken When the MIL/DTC Sets

One or more of the following actions may occur:

* The antilock brake system (ABS), vehicle stability enhancement system (VSES), traction control system (TCS), and dynamic rear proportioning (DRP) are disabled for the duration of the ignition cycle.
* The vehicle dynamics caution (VDC) indicator turns ON.
* The ABS/TCS indicators turn ON.
* The red BRAKE Warning indicator turns ON.
* The driver information center (DIC) displays SERVICE TRACTION CONTROL message.



Conditions for Clearing the MIL/DTC

* The condition for the DTC is no longer present.
* The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.
* The ABS indicator may remain illuminated after the DTCS are cleared, until the vehicle is operated at speeds greater than 13 km/h (8 mph) and the self test is completed.



Diagnostic Aids

Verify that the EBCM power and ground circuits are good if the DTC C0550 is stored in history.


Reference Information
Schematic Reference

Antilock Brake System Schematics ([1][2]Antilock Brakes / Traction Control Systems)
Connector End View Reference

Component Connector End Views
Description and Operation

ABS Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing
* Connector Repairs
* Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs

Scan Tool Reference

Control Module References for Scan Tool Information


Circuit/System Verification

Verify that DTC C0550 is not set.

If the DTC is set, clear the DTC with a scan tool, and operate the vehicle within the conditions for setting the DTC. If the DTC resets, replace the EBCM.



Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.


Control Module References for EBCM replacement, setup, and programming