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.

NOTE: The vehicle may be equipped with sectioned coax. Test each section and replace only the faulty section, not the entire length of coax.

Ignition OFF, disconnect the cellular antenna coax from the CIM module and the cellular antenna.
Connect the EL-49903 to the CIM, place the test antenna on the roof of the vehicle. See Special Tools .
Ignition ON, clear the DTCs and operate the vehicle within the conditions for running the DTC. Verify B2470 does not set
- if the DTC sets, replace the CIM.
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.