GM Service Manual Online
For 1990-2009 cars only

Circuit Description

When the radio is powered up, the radio supplies low level audio signals to the speakers. If the vehicle is equipped with an audio amplifier, the amplifier will boost the signal sent to the speakers.

Conditions for Running the DTC

The test is performed when the radio switches from OFF to ON. The radio will continue to test for the fault once every 0.5 seconds.

Conditions for Setting the DTC

The radio sets a current status for this DTC when a short to ground or voltage is detected on any of the speaker channels for 1.5 seconds.

Action Taken When the DTC Sets

No sound is present from one or more of the speakers.

Conditions for Clearing the DTC

The fault condition is not present for 5 seconds.

Step

Action

Yes

No

Schematic Reference: Radio/Audio System Schematics

1

Did you perform the Entertainment System Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Entertainment System

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With the scan tool, monitor the DTC Information for DTC B1025, B1035, B1045 or B1055.

Does the scan tool indicate that DTC B1025, B1035, B1045 or B1055 is current?

Go to Step 3

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

3

Test the speaker outputs from the radio for short to ground or voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 6

Go to Step 4

4

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 6

Go to Step 5

5

Important: Reprogram the radio. Refer to Service Programming System (SPS) in Programming.

Replace the radio. Refer to Radio Replacement .

Did you complete the replacement?

Go to Step 6

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6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2