Circuit/System Testing
WARNING: This page is about a different car, the 2010 GMC Sierra, 2010 GMC Cab & Chassis Sierra, 2010 Chevrolet Silverado, and 2010 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
- Ignition OFF, disconnect the X1 harness connector of the IAH.
- Turn ON the ignition and measure between temperature signal circuit terminal 1 of the connector and a good ground for 2-3 volts.
- If greater than the specified range, test the temperature signal circuit for a short to voltage. If the circuit tests normal, replace the GPCM.
- If less than the specified range, test the temperature signal circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the GPCM.
- If the temperature signal circuit tests normal, replace the IAH.