Mast Antennas
Unplug antenna lead-in connector from radio receiver and plug a test antenna into radio. Make sure 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 antenna and/or lead-in cable. If the reception is still poor, refer to Audio System Troubleshooting Hints.
| Callout | Component Name |
|---|---|
| 1 | Negative Battery Cable |
| 2 | Coaxial Cable Conductor - Radio End |
| 3 | Coaxial Cable Metal Outer Shield - Radio End |
| 4 | Coaxial Cable Metal Outer Shield - Antenna End |
| 5 | Coaxial Cable Conductor - Antenna End |
| 6 | Antenna Base |
| 7 | Antenna Mast |
| 8 | Antenna Coaxial Cable |
Radio Poor Reception
| Ohmmeter Probes At Points | Resistance Measured In Ohms |
|---|---|
| 1 and 3 | Less than 0.2 |
| 1 and 4 | Less than 0.2 |
| 1 and 6 | Less than 0.2 |
| 1 and 2 | Infinite |
| 1 and 5 | Infinite |
| 1 and 7 | Infinite |
| 2 and 3 | Infinite |
| 2 and 4 | Infinite |
| 2and 6 | Infinite |
| 3 and 4 | Less than 0.2 |
| 3and 6 | Less than 0.2 |
| 3 and 5 | Infinite |
| 3 and 7 | Infinite |
Refer to the table when testing the antenna and/or lead-in cable.
- Measure the resistance from the coax center conductor to antenna mast.
- Total resistance from end to end of center conductor:
- RG-58/RG-59 type cable - less than 0.20 Ω
- RG-62/RG-62M type cable - less than 3.5 Ω
- When checking the resistance, cautiously wiggle the lead-in tip and cable. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS .
- Measure the resistance from the cable center conductor to metal case.
- Replace the antenna and/or lead-in cable when the above readings are not obtained.