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 B2745: Traction Control Switch CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
TCS Switch Signal Circuit | B2745 | 1 | -- | -- |
1. Traction control cannot be manually disabled. | ||||
Circuit/System Description
The driver may disable the Traction Control System (TCS) by pressing the traction control switch. The body control module (BCM) supplies a 12-volt signal on the traction control signal circuit. When the traction control switch is pressed, this voltage signal is grounded.
Conditions for Running the DTC
The ignition is ON.
Conditions for Setting the DTC
The BCM detects low voltage on the traction control signal circuit for 60 seconds.
Action Taken When the DTC Sets
| • | The BCM sends a serial data message to the electronic brake control module (EBCM) informing the EBCM that the desired TCS state cannot be determined. |
| • | The EBCM defaults the TCS status to enabled. |
Conditions for Clearing the DTC
The DTC clears automatically from Current status when the fault is corrected. Use a scan tool to clear the DTC from history status.
Diagnostic Aids
An intermittent short to ground on the traction control signal circuit is the most likely cause of a history DTC when no problem is found. When the Conditions for Setting this DTC are present, the driver is not able to disable traction control.
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Traction control can be disabled/enabled when the traction control switch is pressed and released.
Circuit/System Testing
- Turn OFF the ignition for 5 seconds, then turn ON the ignition and wait at least 60 seconds.
- Turn the ignition OFF. Disconnect the traction control switch harness connector. Turn the ignition ON and wait at least 60 seconds.
| ⇒ | If DTC B2745 does not reset, go to Diagnostic Aids. |
| ⇒ | If DTC B2745 does not reset, replace the traction control switch. |
| ⇒ | If the DTC B2745 resets, check the TCS switch signal circuit for a short to ground or replace the BCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
