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For 1990-2009 cars only

DTC B1025, B1035, B1045, or B1055 With RPO WBM


Object Number: 1273899  Size: MF
Entertainment Component Views
Radio/Audio System Schematics w/U2K

Circuit Description

When the radio is set at minimum volume, the plus (+) and minus (-) speaker outputs are approximately 5-6 volts measured to vehicle ground. As the volume increases, the plus and minus change to create a voltage difference between each other. This drives the voice coil of the speaker producing sound.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC B1025 LF Audio Output (+) Circuit
    • DTC B1035 RF Audio Output (+) Circuit
    • DTC B1045 LR Audio Output (+) Circuit
    • DTC B1055 RR Audio Output (+) Circuit

This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to DTC Symptom Description in Vehicle DTC Information.

DTC Symptom

DTC Symptom Descriptor

01

Short to Battery

02

Short to Ground

04

Open Circuit

Conditions for Running the DTC

B1025-B1055 01, 02, and 04

The following are conditions that must be present in order for the radio to enable the diagnostics.

    • The vehicle power mode is ACCESSORY, RUN, or retained accessory power (RAP).
    • The system voltage is at least 9 volts and no more than 16 volts.
    • All the above conditions are present for greater than 250 milliseconds.

Conditions for Setting the DTC

The following conditions are present for 250 milliseconds or longer:

B1025-B1055 01

One of the speaker positive output circuits is shorted to battery.

B1025-B1055 02

The speaker positive output circuit is shorted to ground.

B1025-B1055 04

The speaker positive output circuit is open.

Action Taken When the DTC Sets

The radio disables the audio output to the speaker with the current fault.

Conditions for Clearing the DTC

    • The Conditions for Setting the DTC are no longer present.
    • A history DTC clears after 100 malfunction-free ignition cycles.
    • The radio receives the clear code command from the scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step verifies that the DTC is still present.

  2. This step isolates the fault condition.

Step

Action

Yes

No

Schematic Reference: Radio/Audio System Schematics

Connector End View Reference: Entertainment Connector End Views

1

Did you review the Description and Operation?

Go to Step 2

Go to Radio/Audio System Description and Operation

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 affected speaker output channel from the radio to the speaker for a short to ground, short to voltage, or an open circuit. 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: Perform the radio setup procedure for the radio.

Replace the radio. Refer to Radio Replacement and Radio Setup .

Did you complete the replacement?

Go to Step 6

--

6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

DTC B1025, B1035, B1045, or B1055 Without RPO WBM


Object Number: 1273900  Size: MF
Entertainment Component Views
Radio/Audio System Schematics w/WBM

Circuit Description

When the radio is set at minimum volume, the plus (+) and minus (-) speaker outputs are approximately 5-6 volts measured to vehicle ground. As the volume increases, the plus and minus change to create a voltage difference between each other. This drives the voice coil of the speaker producing sound.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC B1025 LF Audio Output (+) Circuit
    • DTC B1035 RF Audio Output (+) Circuit
    • DTC B1045 LR Audio Output (+) Circuit
    • DTC B1055 RR Audio Output (+) Circuit

This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to DTC Symptom Description in Vehicle DTC Information.

DTC Symptom

DTC Symptom Descriptor

01

Short to Battery

02

Short to Ground

04

Open Circuit

Conditions for Running the DTC

B1025-B1055 01, 02, and 04

The following are conditions that must be present in order for the radio to enable the diagnostics.

    • The vehicle power mode is ACCESSORY, RUN, or retained accessory power (RAP).
    • The system voltage is at least 9 volts and no more than 16 volts.
    • All the above conditions are present for greater than 250 milliseconds.

Conditions for Setting the DTC

The following conditions are present for 250 milliseconds or longer:

B1025-B1055 01

One of the speaker positive output circuits is shorted to battery.

B1025-B1055 02

The speaker positive output circuit is shorted to ground.

B1025-B1055 04

The speaker positive output circuit is open.

Action Taken When the DTC Sets

The radio disables the audio output to the speaker with the current fault.

Conditions for Clearing the DTC

    • The Conditions for Setting the DTC are no longer present.
    • A history DTC clears after 100 malfunction-free ignition cycles.
    • The radio receives the clear code command from the scan tool.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step verifies that the DTC is still present.

  2. This step isolates the fault condition.

Step

Action

Yes

No

Schematic Reference: Radio/Audio System Schematics

Connector End View Reference: Entertainment Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

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 affected speaker output channel from the radio to the amplifier for a short to ground, short to voltage, or an open circuit. 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

Replace the radio. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 6

--

6

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2