Schematic Reference: Radio/Audio System Schematics

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

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Go to Step  2

Go to Diagnostic System Check - Entertainment System

1. Turn ON the ignition, with the engine OFF.
2. Turn ON the radio.
3. Operate all of the steering wheel control (SWC) buttons.

Do all of the steering wheel control buttons operate properly?

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

Go to Step  3

Caution: Refer to SIR Caution in the Preface section.

1. Disable the SIR. Refer to SIR Disabling and Enabling in SIR.
2. Disconnect the SWC connector.
3. Turn ON the ignition, with the engine OFF.
4. Turn ON the radio.
5. Measure the voltage from the supply voltage circuit of the remote radio control to ground.

Does the voltage measure near the specified value?

9.5 V

Go to Step 4

Go to Step  5

1. Measure the resistance from the remote radio control supply voltage circuit of the SWC to the steering wheel controls signal circuit of the SWC.
2. Press the following steering wheel control buttons and record the resistance values:

•

Volume Up

•	Volume Down

•

Play

•

Mute

•

Seek Up

•

Seek Down

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AM/FM

•

Pre-Set

Do the recorded resistances measure near the specified values?

1270 ohms

1564 ohms

1912 ohms

2387 ohms

3102 ohms

4282 ohms

6652 ohms

13,632 ohms

Go to Step  6

Go to Step  7

Test the remote radio control supply voltage circuit between the SWC harness connector and the radio for an open, for a high resistance, or for a short. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step  11

Go to Step  8

1. Disconnect the radio connector. Refer to Radio Replacement .
2. Test the steering wheel controls signal circuit between the SWC harness connector and the radio connector for an open, for a high resistance, or for a short. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step  11

Go to Step  8

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

Did you find and correct the condition?

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Go to Step  11

Go to Step  9

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

Did you find and correct the condition?

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Go to Step  11

Go to Step  10

Replace the SWC switch. Refer to Steering Wheel Control Switch Assembly Replacement in Steering Wheel and Column.

Did you complete the replacement?

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Go to Step  11

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Important: Perform the set up procedure for the radio.

Replace the radio. Refer to Radio Replacement .

Did you complete the replacement?

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Go to Step  11

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Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

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