1. Turn the ignition OFF.
2. Disconnect the antenna lead-in connector at the radio receiver.
3. With a J 39200 digital multimeter (DMM), measure the resistance between the coax (outer conductor) radio and the negative battery cable.

Is the resistance less than the specified value?

0.15 ohms

Go to Step 2

Go to Step 3

1. Grasp the antenna mast.
2. Wiggle the antenna while observing the J 39200 DMM.

Does the DMM indicate intermittent continuity?

--

Go to Step 3

Go to Step 5

Inspect the following connections:

Was a problem with the ground circuit found?

--

Go to Step 4

--

Repair the antenna ground circuit, as needed.

Is the repair complete?

--

System OK

Go to Step 5

With a J 39200 DMM, measure the resistance between the radio coaxial lead-in (center conductor) and the antenna mast.

Is the resistance less than 2 ohms for coax type RG-58 or RG-59, or less than 3.5 ohms for coax type RG-62 or RG-62M?

--

Go to Step 6

Go to Step 7

Observe the J 39200 DMM while wiggling the antenna coax.

Does the J 39200 DMM indicate intermittent continuity?

--

Go to Step 7

Go to Step 8

1. Test the coaxial cable interconnects for a poor connection or corrosion.
2. Repair or replace the antenna coaxial circuit, as needed. Refer to Radio Antenna Replacement .

Is the antenna operative?

--

System OK

Go to Step 8

Refer to Audio Preliminary Diagnosis .

Is the antenna operative?

--

System OK

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