B1035

DTC B1025, B1035, B1045, or B1055

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B1025 01
- Audio Output 1 Left Front Circuit

DTC B1035 01
- Audio Output 2 Right Front Circuit

DTC B1045 01
- Audio Output 3 Left Rear Circuit

DTC B1055 01
- Audio Output 4 Right Rear Circuit

Diagnostic Fault Information






Circuit/System Description

Each of the audio output channel circuits (+) and (-), at the radio and at the amplifier (if equipped) have a DC bias voltage that is one half of the battery voltage. When using a DMM, each of the audio output channel circuits will measure approximately 6.5V DC. The audio being played on the system is produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone to move and produce sound. This voltage will vary depending on what type of audio is being listened to, talk or music, and type of music, as well as the volume setting of the system. Low volume and talk settings will measure around 1V AC and less, where constant music may measure 3V AC and slightly higher. In an amplified audio system, these similar AC voltage measurements may be slightly higher on the output of the amplifier, and the typical AC voltage readings at the output of the radio are less than 1V AC.

Conditions for Running the DTC

The radio is ON.

Conditions for Setting the DTC

A short to voltage or short to ground is detected on the specified (+) or (-) signal circuit

Action Taken When the DTC Sets

The radio disables audio output on the appropriate channel

Conditions for Clearing the DTC

* A current DTC will clear when the conditions for setting are no longer seen
* A history DTC will clear after 100 malfunction free ignition cycles

Circuit/System Verification

Radio ON, adjust the fade and balance controls on the radio to test all four channels individually. Each of the four channels should produce clear and even sound.

Circuit/System Testing

Without Amplifier
1. Ignition OFF, disconnect the harness connector at the appropriate speaker.
2. Radio ON, test for 5.0-7.5 volts between the signal circuit terminal A and ground.

^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
^ If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.

3. Test for 5.0-7.5 volts between the signal circuit terminal B and ground.

^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
^ If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.

4. If all circuits test normal, test or replace the speaker.

With Amplifier
1. Ignition OFF, disconnect the X2 and X3 harness connectors at the amplifier.
2. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left front door or tweeter - Connector X2, terminal 3
* Right front door or tweeter - Connector X2, terminal 1
* Left rear speaker - Connector X2, terminal 7
* Left rear subwoofer - Connector X3, terminal 3
* Right rear speaker - Connector X2, terminal 5
* Right rear subwoofer - Connector X3, terminal 2

^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
^ If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.

3. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left front door or tweeter - Connector X2, terminal 4
* Right front door or tweeter - Connector X2, terminal 2
* Left rear speaker - Connector X2, terminal 8
* Left rear subwoofer - Connector X3, terminal 7
* Right rear speaker - Connector X2, terminal 6
* Right rear subwoofer - Connector X3, terminal 6

^ If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
^ If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.

4. If all circuits test normal, replace the amplifier.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

* Speaker Replacement Reference