Diagnostic Check - Antenna

1. Disconnect the antenna from the extension cable.
2. Plug in a test antenna.
3. Ground the antenna to the vehicle chassis.
4. Do not touch the antenna.
5. Test the radio reception in an area away from electrical interference such as the following items:
^ Tall buildings Metal structures
^ Power lines
^ Florescent lighting
^ Power tools
6. Tune into the high and the low ends of the radio dial on both FM and AM, checking for weak and strong station reception.
7. If the reception is satisfactory, the problem exists in the antenna and/or the lead-in cable.


Testing For Good Ground Of Antenna Mounting And Connections
^ Poor grounds at the antenna mounting, or any other connection in the antenna/lead-in system, can result in seriously reduced radio performance.
^ A poor ground can be a reason for excess ignition noise on AM or bad audio.
^ Make sure that the lead-in connectors are free of dirt and corrosion, and are tightly fastened.
^ Possible ground loss or high-resistance ground points include the following steps:
- Antenna upper mounting (loose screws, paint overspray, etc.)
- Lead-in cable connector at the antenna, (loose or internally corroded)
- Lead-in cable connector at the antenna (loose or internally corroded)
- Quick connect connector (corroded)
- Missing ground lead

Measuring Resistance With A Digital Multimeter

Antenna Diagnostic Check:

^ Usually, a broken center conductor of the lead-in cable will result in no AM and weak FM radio stations.
^ In case of continued reception or noise complaints, always check the lead-in with an ohmmeter.
^ When checking resistance, wiggle the lead-in tip (3) and cable (4).
1. If the readings shown in the accompanying table are not obtained, some portion of the lead-in is intermittent.
2. Replace the lead-in.