Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | 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 Short to BatteryDTC 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 | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Antenna 14V Switched Supply Voltage | 2 | 2 | -- | -- |
Amplifier Battery Positive Voltage | 2 | 2 | -- | -- |
Amplifier Ground | -- | 2 | -- | -- |
Left Front Speaker Output (+)/Left Front Low Level Audio Signal (+) | B1025 02* | 1 | B1025 01* | -- |
Left Front Speaker Output (-)/Left Front Low Level Audio Signal (-) | B1025 02* | 1 | B1025 01* | -- |
Right Front Speaker Output (+)/Right Front Low Level Audio Signal (+) | B1035 02* | 1 | B1035 01* | -- |
Right Front Speaker Output (-)/Right Front Low Level Audio Signal (-) | B1035 02* | 1 | B1035 01* | -- |
Left Rear Speaker Output (+)/Left Rear Low Level Audio Signal (+) | B1045 02* | 1 | B1045 01* | -- |
Left Rear Speaker Output (-)/Left Rear Low Level Audio Signal (-) | B1045 02* | 1 | B1045 01* | -- |
Right Rear Speaker Output (+)/Right Rear Low Level Audio Signal (+) | B1055 02* | 1 | B1055 01* | -- |
Right Rear Speaker Output (-)/Right Rear Low Level Audio Signal (-) | B1055 02* | 1 | B1055 01* | -- |
1. No or reduced sound from speaker 2. Amplifier inoperative/no sound from speakers * Noticeable audio distortion possible | ||||
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
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
| • | 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 |
Reference Information
Schematic Reference
Radio/Navigation System Schematics
Connector End View Reference
Description and Operation
Radio/Audio System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
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
- Ignition OFF, disconnect the harness connector at the appropriate speaker.
- Radio ON, test for 5.0-7.5 volts between each signal circuit terminal A and terminal B and ground.
- If all circuits test normal, replace the speaker.
| ⇒ | 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. |
With Amplifier
- Ignition OFF, disconnect the X1 connector at the amplifier.
- Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.
- If all circuits test normal, replace the amplifier.
| • | Left front low level audio signal (+) - terminal 15 X1 |
| • | Left front low level audio signal (-) - terminal 7 X1 |
| • | Right front low level audio signal (+) - terminal 14 X1 |
| • | Right front low level audio signal (-) - terminal 6 X1 |
| • | Left rear low level audio signal (+) - terminal 13 X1 |
| • | Left rear low level audio signal (-) - terminal 5 X1 |
| • | Right rear low level audio signal (+) - terminal 12 X1 |
| • | Right rear low level audio signal (-) - terminal 4 X1 |
| ⇒ | 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. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for radio or amplifier replacement, setup, and programming |
