B1025
DTC B1025, B1035, B1045, or B1055
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provide an overview of each diagnostic category.
DTC Descriptors
DTC B1025 01
- Audio Output 1 Left Front Circuit Short to Battery
DTC B1025 02
- Audio Output 1 Left Front Circuit Short to Ground
DTC B1035 01
- Audio Output 2 Right Front Circuit Short to Battery
DTC B1035 02
- Audio Output 2 Right Front Circuit Short to Ground
DTC B1045 01
- Audio Output 3 Left Rear Circuit Short to Battery
DTC B1045 02
- Audio Output 3 Left Rear Circuit Short to Ground
DTC B1055 01
- Audio Output 4 Right Rear Circuit Short to Battery
DTC B1055 02
- Audio Output 4 Right Rear Circuit Short to Ground
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.
Conditions for Running the DTC
The radio is ON.
Conditions for Setting the DTC
B1025 01, B1035 01, B1045 01, B1055 01
A short to voltage is detected on the specified (+) or (-) signal circuit.
B1025 02, B1035 02, B1045 02, B1055 02
A 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
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.
Diagnostic Aids
Speakers located in the front A-pillar are connected to the same channel as the speaker in the door.
Reference Information
Schematic Reference
Radio/Navigation System Schematics (Radio/Navigation System Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Radio/Audio System Description and Operation (Radio/Audio System Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Verification
Radio ON, adjust the fade and balance controls on the radio and listed to each of the four audio channels individually. Each of the four channels should produce clear and even sound.
Circuit/System Testing
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 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.
• If greater than the specified range, test the signal circuit for a short to voltage. 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 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.
• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.
4. If all circuits test normal, replace the speaker.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Speaker Replacement Reference (Speaker Replacement Reference)
* Control Module References (Programming and Relearning) for Radio replacement, setup, and programming