Component 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.
Sliding Rear Window Switch Test
- Ignition OFF, disconnect the harness connector at the sliding rear window switch.
- Test for infinite resistance between the control terminals C and B and the voltage terminal A with the switch in the INACTIVE position.
- If less than the specified value, replace the sliding rear window switch.
- Test for less than 2 ohms between the control terminal C and the voltage terminal A with the switch in the CLOSE position.
- If greater than the specified range, replace the sliding rear window switch.
- Test for less than 2 ohms between the control terminal B and the voltage terminal A with the switch in the OPEN position.
- If greater than the specified range, replace the sliding rear window switch.
Relay Test
- Ignition OFF, disconnect the applicable relay.
- Test for 60-200 ohms between terminals 85 and 86.
- If not within the specified range, replace the relay.
- Test for infinite resistance between the following terminals:
- 30 and 86
- 30 and 87
- 30 and 85
- 85 and 87
- If not the specified value, replace the relay.
- Test for less than 2 ohms between terminals 30 and 87A.
- If greater than the specified range, replace the relay.
- Install a 3-amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms of resistance between terminals 30 and 87.
- If greater than the specified range, replace the relay.
Sliding Rear Window Motor
- Install a 25-amp fused jumper wire between the control terminal A and 12 volts. Momentarily install a jumper wire between the control terminal B and ground. The sliding rear window motor should perform the OPEN or CLOSE function.
- If the function does not perform as specified, replace the sliding rear window motor.
- Reverse the jumper wires; the sliding rear window motor should perform the CLOSE or OPEN function.
- If the function does not perform as specified, replace the sliding rear window motor.