Circuit/System Testing
- Ignition ON, verify that the Stop Lamp Pedal Switch parameter in the ECM reads Applied while depressing the brake pedal.
- If the Stop Lamp Pedal Switch parameter reads Released, test the stop lamp switch signal circuit for an open/high resistance, a short to ground, or a short to voltage. If the circuit tests normal, replace the BCM.
- If all circuits test normal, replace the ECM.