For 1990-2009 cars

### 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 C0561 71: CAN-Bus Invalid Data

### Circuit/System Description

The electronic brake control module (EBCM) receives messages from the engine control module (ECM), and the transmission control module (TCM) over GMLAN which are needed to perform ESP or TCS functions.

### Conditions for Running the DTC

• | Ignition ON.

• | Ignition voltage is greater than 8 volts.

### Conditions for Setting the DTC

The EBCM receives an invalid message from either the ECM or TCM over GMLAN which causes EBCM to deactivate TCS, ESP and EBD.

### Action Taken When the DTC Sets

• | The EBCM disables the Traction Control System (TCS)/Electronic Stability Control (ESP) for the duration of the ignition cycle.

• | A multi function display (MFD) message and/or a warning indicator may be displayed.

### Conditions for Clearing the DTC

The condition for setting the DTC is no longer present.

### Reference Information

#### Schematic Reference

Antilock Brake System Schematics

#### Connector End View Reference

Component Connector End Views

#### 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 Testing

Verify that no DTCs are set in the ECM or TCM.

⇒ | If DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.