Using a Test Antenna
WARNING: This page is about a different car, the 2008 Cadillac SRX. However, it is still accessible from the selected car via links, so may be relevant.
Use a test mast antenna to check for poor vehicle antenna operation. Disconnect the antenna coax from the radio and plug the test antenna into radio. Make sure the test antenna base is grounded to the vehicle chassis and keep hands off the mast. Check radio reception in an area away from electrical interferences. Tune to several weak and strong AM and FM stations. If the radio reception improved, the problem exists with the vehicle antenna and/or lead-in cable. If the reception is still poor, refer to Speaker Malfunction .