Antilock Brake System - Non-Hybrid Less than 3900 kg (8600 lb) GVW

DTC C0561

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptor
DTC C0561 71
- System Disabled Information Stored Invalid Serial Data Received

DTC C0561 72
- System Disabled Information Stored Alive Counter Incorrect or not Updated

DTC C0561 74
- System Disabled Information Stored Value of Signal Protection Calculation Incorrect

Circuit/System Description

The electronic brake control module (EBCM) receives messages from other modules over GMLAN which are needed to perform antilock brake system (ABS), vehicle stability enhancement system (VSES), or traction control system (TCS) functions.

Conditions for Running the DTC

* The ignition switch is in the ON position.
* Ignition voltage is greater than 9.5 volts.

Conditions for Setting the DTC

The EBCM receives an invalid message from another module over GMLAN which causes EBCM to deactivate ABS, VSES, TCS, etc.

Action Taken When the DTC Sets

One or more of the following actions may occur:

* The EBCM disables the ABS/TCS/VSES for the duration of the ignition cycle.
* The dynamic rear proportioning (DRP) may be disabled and the Brake Warning indicator may turn ON.
* The Stability Caution indicator turns ON.
* The driver information center (DIC) displays the SERVICE STAB SYS message.
* The DIC displays the TRACTION FAILED message.

Conditions for Clearing the 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.

Reference Information
Schematic Reference

Antilock Brake System Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

ABS Description and Operation (ABS (Non-Hybrid Less than 3900 kg (8600 lb) GVW))
Electrical Information Reference

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

Scan Tool Reference

Control Module References (Control Module References) for Scan Tool Information

Circuit/System Verification

Note: Diagnose any other DTCs before attempting to diagnose C0561.

1. With a scan tool, view the EBCM Signal Data Display.
2. If no invalid signal are present, view Invalid Signal Data in the Enhanced DTC Data.
3. Refer to appropriate module for diagnosing the invalid signal data.
4. Do not replace the EBCM due to this DTC fault.