Multifunction Switch Circuit Test
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the X3 harness connector at the turn signal multifunction switch.
- Ignition OFF, test for less than 20 ohms between the low reference circuit terminal M and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
- Verify the scan tool Windshield Wiper Switch parameter is Off.
- If not the specified value, test the signal circuit terminal N for a short to ground. If the circuit tests normal, replace the BCM.
- Verify the scan tool Wiper High Speed Switch parameter is Inactive.
- If not the specified value, test the signal circuit terminal K for a short to ground. If the circuit tests normal, replace the BCM.
- Install a 3-amp fused jumper wire between the signal circuit terminal N and ground. Verify the scan tool Windshield Wiper Switch parameter is Switch Fault.
- 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.
- Install a 3-amp fused jumper wire between the signal circuit terminal K and ground. Verify the scan tool Wiper High Speed 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 BCM.
- If all circuits test normal, replace the turn signal multifunction switch.