• | 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. |
The electronic brake control module (EBCM) and the engine control module (ECM) simultaneously control the traction control. The EBCM sends a serial data message to the ECM requesting torque reduction. When certain ECM DTCs are set, the ECM will not be able to perform the torque reduction for traction control. A serial data message is sent to the EBCM indicating that traction control is not allowed.
• | The ignition is ON. |
• | Ignition voltage is greater than 8 volts. |
The ECM diagnoses a condition preventing the engine control portion of the traction control function and sends a serial data message to the EBCM indicating that torque reduction is not allowed. The ECM will typically set a DTC and the EBCM will set this DTC.
• | The EBCM disables the TCS for the duration of the ignition cycle. |
• | The Traction Off indicator turns ON. |
• | The DIC displays the Service Traction Control message. |
• | The ABS remains functional. |
• | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
• | The electronic brake control module (EBCM) automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Antilock Brake System Schematics
Antilock Brake System Connector End Views
Verify that no DTCs are set in the ECM.
⇒ | If DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.