Antenna Coaxial Cable Testing

Use the appropriate chart and diagram to test the antenna coaxial cable resistances for the antenna system on the vehicle. Refer to the table when testing the antenna and/or lead-in cable.

Fig 1: Mast Antenna System

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Important:  Always zero out the DMM before taking a resistance measurement in order to ensure an accurate reading.

1. Measure the resistance from the coax center conductor to antenna mast, ohmmeter probes at points 2 and 7.
2. Total resistance from end to end of center conductor-ohmmeter probes at points 2 and 5:
   • RG-58/RG-59 type cable - less than 0.20 ohms per foot
   • RG-62/RG-62M type cable - less than 3.5 ohms per foot
3. When checking the resistance, cautiously wiggle the lead-in tip and cable. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS in Wiring Systems.
4. Replace the antenna and/or lead-in cable when the above readings are not obtained.

Fig 2: Radio Poor Reception Specifications

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Fig 3: Radio Displays LOC, LOCKED, Or CODE

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Fig 4: Radio Displays CLN Or CLEAN

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Fig 5: Radio Displays CAL Or CAL ERR

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Fig 6: Tape Player Weak, Slow, Or Garbled Output

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Fig 7: Steering Wheel Controls Inoperative (1 Of 2)

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Fig 8: Steering Wheel Controls Inoperative (2 Of 2)

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