The vehicles covered by these instructions have a wire grid-type antenna on the rear window glass. To troubleshoot radio reception issues, check the antenna wires for continuity using an ohmmeter. Wrap small pieces of aluminum foil around the ohmmeter probes and touch them to the antenna grid wires. Place one probe on an antenna terminal and move the other probe along the wire to check for continuity until a break is found. If a break is detected, repair the wire as you would a rear window defogger wire.