Schematic Reference: Radio/Audio System Schematics

1

Did you perform the Radio/Audio System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Radio/Audio System

1. Turn ON the ignition, with the engine OFF.
2. Turn ON the radio.
3. Insert the tape or CD from the J 39916-A .
4. Adjust the volume to the lowest setting that can be heard.

Is the audio too loud for the lowest setting?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

1. Install a scan tool.
2. Turn ON the ignition with the engine OFF.
3. With a scan tool, observe the Amplifier data parameter in the Radio System Configuration data list.

Does the scan tool indicate that the Amplifier data parameter is present?

Go to Step 4

Go to Step 5

Compare the volume to a similar vehicle with the same audio system.

Are both vehicles the same?

System OK

Go to Step 7

1. Turn OFF the ignition.
2. Test the Gain Control Signal Circuit between the radio and the audio amplifier for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 6

1. Turn OFF the ignition.
2. Disconnect the audio amplifier connector. Refer to Radio Speaker Amplifier Replacement for service procedure.
3. Connect a 3 amp fused jumper from the Gain Control Signal Circuit of the audio amplifier and a good ground.
4. Does the scan tool indicate that the Amplifier data parameter is Present?

Go to Step 8

Go to Step 7

Inspect for poor connections at the harness connector of the radio. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 9

Inspect for poor connections at the harness connector of the audio amplifier. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 10

Important:: Perform the setup procedure for the radio.

Replace the radio. Refer to Radio Replacement and Radio Setup for service procedure.

Did you complete the replacement?

Go to Step 11

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Replace the audio amplifier. Refer to Radio Speaker Amplifier Replacement for service procedure.

Did you complete the replacement?

Go to Step 11

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3