Schematic Reference: Radio/Audio System Schematics

Did you review the Radio/Audio System Description and Operation and perform the necessary inspections?

--

Go to Step 2

Go to Radio/Audio System Description and Operation

1. Turn ON the ignition, with the engine OFF.
2. Turn ON the radio.
3. Tune the radio to a known strong AM station, then tune to a known strong FM station.

Is the radio reception clear?

--

Go to Audio System Troubleshooting Hints

Go to Step  3

Inspect for a poor connection at the radio antenna lead-in connector. Refer to Testing for Intermittent Conditions and Poor Connections and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  12

Go to Step  4

1. Turn OFF the ignition.
2. Disconnect the negative battery cable.
3. Remove the radio. Refer to Radio Replacement .

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

4. Measure the resistance between the negative battery cable and the radio antenna coaxial ground at the radio.

Does the resistance measure greater than the specified value?

0.20 ohms

Go to Step 5

Go to Step  6

Inspect the base of the antenna for a proper connection to body ground. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  12

Go to Step  7

1. Grasp the antenna mast.
2. Monitor the DMM and wiggle the antenna mast.
3. Continue to monitor the DMM and wiggle the radio antenna coaxial cable.

Does the DMM display intermittent continuity?

--

Go to Step  8

Go to Step  9

Test for an open or high resistance from the battery negative cable to body ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  12

Go to Step  10

1. Inspect the base of the antenna for a proper connection to body ground.
2. Inspect the antenna coaxial cable interconnects for a poor connection or corrosion. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Did you find and correct the condition?

--

Go to Step  12

Go to Step  10

1. Remove the antenna coaxial lead-in connector from the radio.
2. Measure the resistance between the antenna coaxial lead-in connector (center conductor) and the antenna mast. Refer to Circuit Testing in Wiring Systems.

Does the resistance measure greater than the specified values?

RG-58/RG-59 Coax: 0.2 ohms

RG-62/RG-62M Coax: 3.5 ohms

Go to Step  10

Go to Step  11

Replace the antenna coaxial cable. Refer to Radio Antenna Replacement .

Did you complete the replacement?

--

Go to Step  12

--

1. Test for continuity between the antenna coaxial cable center conductor and metal case.
2. Test at the opposite end of the antenna cable also.

Did you measure continuity?

--

Go to Step  10

Go to Audio System Troubleshooting Hints

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2