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
Ignition 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. |
| • | A DIC message and/or warning message may be displayed. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information.
Circuit/System Verification
Ignition ON, observe the scan tool BCM Traction Control Switch parameter while pressing and releasing the Traction Control Switch. The reading should change between Pressed and Released.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the traction control switch.
- Test for less than 5 ohms between the ground circuit terminal 13 and ground.
- Ignition ON, verify the scan tool Traction Control Switch State parameter is Released.
- Install a 3A fused jumper wire between the signal circuit terminal 14 and the ground circuit terminal 13. Verify the scan tool Traction Control Switch State parameter is Pressed.
- If all circuits test normal, test or replace the traction control switch.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | If not the specified value, test the signal circuit terminal 14 for a short to ground. If the circuit tests normal, replace the BCM. |
| ⇒ | If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM. |
Component Testing
- Ignition OFF, disconnect the harness connector at the traction control switch.
- Test for infinite resistance between the signal terminal 14 and the ground terminal 13 with the switch in the open position.
- Test for less than 3 ohms between the signal terminal 14 and the ground terminal 13 with the switch in the closed position.
| ⇒ | If not the specified value, replace the traction control switch. |
| ⇒ | If greater than the specified range, replace the traction control switch. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, setup, and programming |
