Circuit/System Testing
WARNING: This page is about a different car, the 2008 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
- With a scan tool clear the DTC.
- Ignition OFF, disconnect the harness connector at the I/P Dimmer switch.
- Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal 10.
- If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
- Verify the scan tool dimming control signal parameter is less than 0.2 volts.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
- Install a 3-A fused jumper wire between the signal circuit terminal 9 and the B+ voltage reference circuit terminal 5. Verify the scan tool dimming control signal parameter is greater than 3.5 volts.
- If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
- If all circuits test normal, test or replace the I/P dimmer switch.