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 B1025 04: Audio Output 1 Left Front Circuit Open
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 B1035 04: Audio Output 2 Right Front Circuit Open
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 B1045 04: Audio Output 3 Left Rear Circuit Open
DTC B1055 01: Audio Output 4 Right Rear Circuit Short to Battery
DTC B1055 02: Audio Output 4 Right Rear Circuit Short to Ground
DTC B1055 04: Audio Output 4 Right Rear Circuit Open
DTC B1065 01: Audio Output 5 Circuit Short to Battery (Center IP)
DTC B1065 02: Audio Output 5 Circuit Short to Ground (Center IP)
DTC B1065 04: Audio Output 5 Circuit Open (Center IP)
DTC B1075 01: Audio Output 6 Circuit Short to Battery (Subwoofer)
DTC B1075 02: Audio Output 6 Circuit Short to Ground (Subwoofer)
DTC B1075 04: Audio Output 6 Circuit Open (Subwoofer)
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Amplifier Battery Positive Voltage | 1 | 1 | -- | -- |
Amplifier Control | B1287 02 | B1287 04 | B1287 01 | -- |
Amplifier Ground | -- | 1 | -- | -- |
Antenna 14V switched Supply Voltage | 1 | 1 | -- | -- |
Left Front Low Level Audio Signal (+)/Left Front Speaker Signal (+) | B1025 02* | B1025 04* | B1025 01* | -- |
Left Front Low Level Audio Signal (-)/Left Front Speaker Signal (-) | B1025 02* | B1025 04* | B1025 01* | -- |
Right Front Low Level Audio Signal (+)/Right Front Speaker Signal (+) | B1035 02* | B1035 04* | B1035 01* | -- |
Right Front Low Level Audio Signal (-)/Right Front Speaker Signal (-) | B1035 02* | B1035 04* | B1035 01* | -- |
Left Rear Low Level Audio Signal (+)/Left Rear Speaker Signal (+) | B1045 02* | B1045 04* | B1045 01* | -- |
Left Rear Low Level Audio Signal (-)/Left Rear Speaker Signal (-) | B1045 02* | B1045 04* | B1045 01* | -- |
Right Rear Low Level Audio Signal (+)/Right Rear Speaker Signal (+) | B1055 02* | B1055 04* | B1055 01* | -- |
Right Rear Low Level Audio Signal (-)/Right Rear Speaker Signal (-) | B1055 02* | B1055 04* | B1055 01* | -- |
Front Center Speaker (+) | B1065 02* | B1065 04* | B1065 01* | -- |
Front Center Speaker (-) | B1065 02* | B1065 04* | B1065 01* | -- |
Subwoofer Audio Signal (+) | B1075 02* | B1075 04* | B1075 01* | -- |
Subwoofer Audio Signal (-) | B1075 02* | B1075 04* | B1075 01* | -- |
1. Amplifier inoperative/no sound from speakers * Speaker output DTCs available when equipped with amplifier UQA only | ||||
Circuit/System Description
Each of the audio output channel circuits (+) and (-), at the radio and at the amplifier 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.
Amplifier UQA
The radio provides left and right audio signals to the amplifier. The amplifier is supplied battery voltage from a dedicated fuse in the rear fuse block. The amplifier communicates with the vehicle via serial data, which controls the power state of the amplifier and allows the amplifier to set DTCs. Balance/fade and muting functions are all performed by the amplifier based on serial data messages.
Amplifier UQ3
The radio provides four channels of audio signals to the amplifier- left front, left rear, right front and right rear. The amplifier is supplied battery voltage from a dedicated fuse in the rear fuse block. The amplifier power state is controlled by a remote enable signal via the antenna 14V switched supply circuit, which also provides power to the antenna module. Amplifier muting functions are controlled by a dedicated pulse width modulated signal from the radio via the amp control circuit. The amplifier provides eight audio output channels to the speakers. This amplifier does not communicate on the serial data bus and cannot set DTCs.
Diagnostic Aids
| • | When equipped with the UQA amplifier, DTCs may be set by the radio for the audio outputs to the amplifier; or by the amplifier, for the audio outputs to the speakers. |
| • | When equipped with the UQ3 amplifier, only the radio sets DTCs for the audio outputs to the amplifier. |
Conditions for Setting the DTC
DTC B1025 01, B1035 01, B1045 01, B1055 01, B1065 01, B1075 01
A short to voltage is detected on the specified (+) or (-) signal circuit
DTC B1025 02, B1035 02, B1045 02, B1055 02, B1065 02, B1075 02
A short to ground is detected on the specified (+) or (-) signal circuit
DTC B1025 04, B1035 04, B1045 04, B1055 04, B1065 04, B1075 04
An open is detected on the specified (+) or (-) signal circuit
Conditions for Setting the DTC
The radio sets a current status for this DTC when a short to ground, short to voltage or an open is detected on any of the 6 speaker channel outputs from the radio.
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. |
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 audio channels individually. All speakers should produce clear and even sound.
DTC set by radio with amplifier UQA
- Ignition OFF, disconnect the X3 harness connector at the audio amplifier.
- Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.
- If the circuit tests normal, replace the audio amplifier.
| • | Left low level audio signal (+) -terminal 11 |
| • | Left low level audio signal (-) -terminal 12 |
| • | Right low level audio signal (+) -terminal 3 |
| • | Right low level audio signal (-) -terminal 4 |
| ⇒ | If greater than the specified range, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the radio. |
| ⇒ | If less than the specified range, test the appropriate signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio. |
DTC set by amplifier with amplifier UQA
- Ignition OFF, disconnect the X1 and X2 harness connectors at the amplifier.
- Ignition ON, test for less than 1 volt between each of the signal circuit terminals listed below and ground.
- Ignition OFF, test for infinite resistance between each of the signal circuit terminals listed below and ground.
- Reconnect all harness connectors at the amplifier. Disconnect the harness connector at the appropriate speaker.
- Radio ON, test for 5.0-7.5 volts between each of the appropriate signal circuit terminals listed below and ground.
- If all circuits test normal, replace the inoperative speaker.
| • | Subwoofer speaker output (+)- terminal 1 X1 |
| • | Subwoofer speaker output (-) -terminal 2 X1 |
| • | Left front speaker output (+)- terminal 4 X2 |
| • | Left front speaker output (-)-terminal 5 X2 |
| • | Right front speaker output (+)- terminal 7 X2 |
| • | Right front speaker output (-) -terminal 6 X2 |
| • | Left rear speaker output (+) -terminal 15 X2 |
| • | Left rear speaker output (-) -terminal 14 X2 |
| • | Right rear speaker output (+)- terminal 16 X2 |
| • | Right rear speaker output (-)- terminal 8 X2 |
| • | Front center speaker output (+) -terminal 13 X2 |
| • | Front center speaker output (-)-terminal 12 X2 |
| ⇒ | If greater than the specified range, test both signal circuits of the affected speaker for a short to voltage. |
| • | Subwoofer speaker output (+)- terminal 1 X1 |
| • | Subwoofer speaker output (-) -terminal 2 X1 |
| • | Left front speaker output (+)- terminal 4 X2 |
| • | Left front speaker output (-)-terminal 5 X2 |
| • | Right front speaker output (+)- terminal 7 X2 |
| • | Right front speaker output (-) -terminal 6 X2 |
| • | Left rear speaker output (+) -terminal 15 X2 |
| • | Left rear speaker output (-) -terminal 14 X2 |
| • | Right rear speaker output (+)- terminal 16 X2 |
| • | Right rear speaker output (-)- terminal 8 X2 |
| • | Front center speaker output (+) -terminal 13 X2 |
| • | Front center speaker output (-)-terminal 12 X2 |
| ⇒ | If less than the specified range, test both signal circuits of the affected speaker for a short to ground. |
| • | Front tweeter speakers - terminals A and B |
| • | Center IP speaker- terminals A and B |
| • | Door speakers - terminals A and B |
| • | Subwoofer speaker - terminals A and B |
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the audio amplifier. |
| ⇒ | 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 audio amplifier. |
With amplifier UQ3
- Ignition OFF, disconnect the X3 harness 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 1 |
| • | Left front low level audio signal (-) -terminal 2 |
| • | Right front low level audio signal (+) -terminal 10 |
| • | Right front low level audio signal (-) -terminal 9 |
| • | Left rear low level audio signal (+) -terminal 4 |
| • | Left rear low level audio signal (-) -terminal 3 |
| • | Right rear low level audio signal (+) -terminal 11 |
| • | Right rear low level audio signal (-) -terminal 12 |
| ⇒ | 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. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for audio amplifier or radio replacement |
