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.
- Ignition OFF, disconnect the cellular antenna coax from the CIM module and the cellular antenna.
- Ignition ON, test for less than 1 volt between the antenna coax center terminal and ground.
- If greater than the specified range, replace the antenna coax.
- Ignition ON, test for less than 1 volt between the antenna coax outer shield and ground.
- If greater than the specified range, replace the antenna coax.
- Test for infinite resistance between the antenna coax center terminal and ground.
- If less than the specified value, replace the antenna coax
- Test for infinite resistance between the antenna coax outer shield and ground.
- If less than the specified value, replace the antenna coax
- Test for less than 5 ohms at the cellular antenna coax center terminal from end to end.
- If greater than specified value, replace the cellular antenna coax cable.
- Test for less than 5 ohms at the cellular antenna coax outer shield from end to end.
- If greater than specified value, replace the cellular antenna coax cable.
- Test for infinite resistance between the antenna coax center terminal and the outer shield.
- If less than specified value, replace the cellular antenna coax cable.
- If coax cable tests normal, replace the cellular antenna.
- Press the OnStar® Call Center button. Verify the system connects to the OnStar® call center.
- If a connection is not made to the OnStar® call center, replace the CIM.