Circuit/System Testing
WARNING: This page is about a different car, the 2010 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect at the S78 turn signal/multifunction switch.
- Ignition ON, verify that the scan tool Headlamps Flash Switch parameter is Inactive.
- If not the specified value, test the signal circuit terminal 4 for a short to ground. If the circuit tests normal, replace the K9 BCM.
- Connect a 3 A fused jumper wire between the signal circuit terminal 4 and ground, verify that the scan tool Headlamps Flash Switch parameter is Active.
- 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 K9 BCM.
- If all circuits test normal, test or replace the S78 turn signal/multifunction switch.