Circuit/System Testing
WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the X1, X4 harness connectors at the MSM.
- Test for infinite resistance between the driver seat heating element supply voltage circuit terminal 14 X1 and ground.
- If less than the specified range, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
- Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 14 X1 and ground.
- If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
- Test for infinite resistance between the passenger seat heating element supply voltage circuit terminal 6 X1 and ground.
- If less than the specified range, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to ground.
- Ignition ON, verify that a test lamp does not illuminate between the supply voltage circuit terminal 6 X1 and ground.
- If the test lamp illuminates, test the supply voltage circuit and the seat cushion and seat back heating element control circuits for a short to voltage.
- If all circuits test normal, replace the MSM.