Antilock Brake System - Non-Hybrid Less than 3900 kg (8600 lb) GVW
DTC B2745
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 Instructionsprovides an overview of each diagnostic category.
DTC Descriptor
DTC B2745 02
- Traction Control Switch Circuit Short to Ground
Diagnostic Fault Information
Circuit/System Description
The body control module (BCM) monitors the traction control switch. When the traction control switch is pressed once, the BCM will request the electronic brake control module (EBCM) via serial data to disable the traction control. The EBCM will request the instrument cluster via serial data to turn the traction control off and stability control off indicator ON to notify the driver of the deactivation.
Conditions for Running the DTC
Ignition ON.
Conditions for Setting the DTC
The BCM detects a short to ground on the signal circuit.
Action Taken When the DTC Sets
The BCM ignores the traction control switch signal input.
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 40 consecutive drive cycles.
Note: During normal diagnostic and/or repair verification technicians may find that the ABS, Traction Control and/or Stabilitrak indicators may be ON with NO DTCs displayed by the EBCM. Do not replace the EBCM for this condition.
If the ABS, Traction Control and/or Stabilitrak telltales are ON with no DTCs set, perform the following steps:
1. Remove the key from the ignition, open and close the driver's door to turn off retained accessory power (RAP), and wait 60 seconds.
2. Ignition ON, if the ABS, Traction Control and/or Stabilitrak telltales are still illuminated, operate the vehicle at speeds greater than 15 km/h (10 mph) to complete the self test. The EBCM should request all telltale indicators to turn OFF.
3. If the telltales remain ON with no DTCs set after the drive cycle, disconnect the battery for at least 60 seconds then reconnect the battery.
4. Operate the vehicle at speeds greater than 40 km/h (25 mph), the EBCM should request all telltale indicators to turn OFF.
Reference Information
Schematic Reference
Antilock Brake System Schematics Non-Hybrid Less than 3900 kg (8600 lb) GVW
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 Programming and Relearningfor scan tool information
Circuit/System Verification
1. Ignition ON, with a scan tool command the IPC display test ON and OFF. The Stabilitrak indicator should turn ON and OFF.
• If the indicator does not turn ON and OFF, replace the instrument panel cluster (IPC).
2. Observe the scan tool BCM Traction Control Switch parameter while pressing and releasing the traction control switch. The reading should change between Active and Inactive.
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector at the traction control switch or the multifunction switch-I/P.
2. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 10 Ohms between the appropriate ground circuit terminal listed below and ground.
* Terminal 3 (with X88 or Z88)
* Terminal 5 (with Z75)
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify the scan tool Traction Control Switch parameter is Inactive.
• If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal, replace the BCM.
4. Install a 3 A fused jumper wire between the signal circuit terminal 1 and the appropriate ground circuit terminal listed below. Verify the scan tool Traction Control Switch parameter is Active.
* Terminal 3 (with X88 or Z88)
* Terminal 5 (with Z75)
• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
5. If all circuits test normal, test or replace the traction control switch or the multifunction switch-I/P.
Component Testing
1. Ignition OFF, disconnect the harness connector at the traction control switch or the multifunction switch-I/P.
2. Test for infinite resistance between the signal terminal 1 and the appropriate ground terminal listed below with the switch in the open position.
* Terminal 3 (with X88 or Z88)
* Terminal 5 (with Z75)
• If not the specified value, replace the traction control switch or the multifunction switch-I/P.
3. Test for less than 5 Ohms between the signal terminal 1 and the appropriate ground terminal listed below with the switch in the closed position.
* Terminal 3 (with X88 or Z88)
* Terminal 5 (with Z75)
• If greater than the specified range, replace the traction control switch or the multifunction switch-I/P.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Electronic Traction Control Switch Replacement
* Control Module References Programming and Relearningfor BCM or IPC replacement, programming and setup