Circuit/System Testing

IMPORTANT: Diagnose all vehicle DTCs before using this diagnostic.
The malfunction must be present during diagnosis in order to prevent unnecessary parts replacement.

Ignition OFF, disconnect the BCM harness at the traction control switch (TCS).
Ignition ON, verify that a test lamp illuminates between the traction control switch signal circuit terminal C and ground.
- If the test lamp does not illuminate, test the TCS control circuit for a short to ground or an open/high resistance. If the circuit tests normal and the control circuit fuse is open, test the signal circuit terminal C for a short to ground.
Verify the scan tool BCM TCS switch data display parameter is Released value.
- If not the specified value, test the signal circuit terminal C for a short to voltage. If the circuit tests normal, replace the body control module (BCM).
Install a 3 A fused jumper wire between the TCS switch signal circuit terminal C and ground. Verify the scan tool BCM TCS switch data display is Pressed value.
- If not the specified value, test the signal circuit terminal C for an open/high resistance. If the circuit tests normal, replace the BCM.
If all circuits test normal, test or replace the traction control TCS switch.