Circuit/System Testing
WARNING: This page is about a different car, the 2008 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.
Antenna Coaxial Cable Testing
- Ignition OFF, disconnect all coax cables from the radio, radio antenna modules, and both antennas in the left and right rear windows.
- Test for infinite resistance between the antenna coax center terminal and ground.
- If less than the specified value, replace the antenna coax.
- Test for less than 5 ohms on the antenna coax center terminal from end to end.
- If greater than the specified range, replace the antenna coax.
- Test for less than 5 ohms on the antenna coax outer shield from end to end.
- If greater than the specified range, replace the antenna coax.
- Test for infinite resistance between the coax center terminal and the outer shield.
- If less than the specified value, replace the antenna coax.
IMPORTANT:
For steps 2-5, perform the tests on each of the disconnected coax cables.
Antenna Inspection
- Ignition OFF, disconnect the coax cables from the antennas located in the left and right rear windows.
- Verify the coax connectors are properly secured and free of any damage.
- If damage is found, repair or replace as necessary.
- Inspect each antenna. Verify all branches of the antennas are intact, with no scratches or other damage.
- If damage is found, repair or replace as necessary.
Radio Antenna Module Test
- Inspect the radio antenna module grounding surface and the mounting hardware for any corrosion that may cause a poor ground.
- If corrosion is noted, clean the grounding surfaces and hardware.
- Ignition OFF, disconnect the X3 harness connector at the radio antenna module.
- Radio ON, test for B+ between the signal circuit terminal A and ground.
- If less than the specified value, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
- If all circuits test normal, replace the radio antenna module.