Speaker Malfunction (UQA)
Speaker Malfunction (UQA)
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provide an overview of each diagnostic category.
DTC Descriptors
DTC B1025
- Audio Output 1 Circuit
DTC B1035
- Audio Output 2 Circuit
DTC B1045
- Audio Output 3 Circuit
DTC B1065
- Audio Output 5 Circuit
DTC B1075
- Audio Output 6 Circuit
DTC B1085
- Audio Output 7 Circuit
For symptom byte information refer to Symptom Byte List Symptom Byte List.
Diagnostic Fault Information
Circuit/System Description
The Media Oriented Systems Transport (MOST) is a high-speed multimedia network technology. The serial MOST bus uses a ring topology and synchronous data communication to transmit audio, video, data and control information between any devices attached.
The audio amplifier is a participant on the MOST network. The audio amplifier receives audio inputs and control information from the MOST bus.
Each of the audio output channel circuits (+) and (-), at the audio amplifier have a DC bias voltage that is approximately 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.
Diagnostic Aids
* Improper speaker mounting or loose trim may cause an audible buzz or distortion. Inspect the appropriate speaker and the surrounding interior trim for proper and secure mounting.
The EL-50334-6 Audio System Diagnostic CD contains audio tracks that can be used to duplicate and isolate such concerns. Tracks 11 and 12 contain audio sweep tones for testing for speaker and grill rattles.
If the speaker or surrounding interior trim is found to be loose or improperly secured, correctly secure the item.
* The test tones on the CD may be copied to a USB drive or other device to use during testing.
* Some audio output circuits are connected to more than one speaker, dependant on vehicle equipment. It may be necessary to disconnect one or more speakers during testing of some circuits.
Conditions for Running the DTC
Note: DTC B1325 must not be set as current for the amplifier to run any of the following tests.
DTC B1025 01, B1035 01, B1045 01, B1065 01, B1075 01, B1085 01
The test is run initially upon amplifier wake-up, and periodically every one second after amplifier operation begins.
DTC B1025 02, B1035 02, B1045 02, B1065 02, B1075 02, B1085 02
The test is run initially upon amplifier wake-up, and periodically every one second after amplifier operation begins.
DTC B1025 04, B1035 04, B1045 04, B1065 04, B1075 04, B1085 04
The test is run once during amplifier wake-up.
Conditions for Setting the DTC
DTC B1025 01, B1035 01, B1045 01, B1065 01, B1075 01, B1085 01
A short to voltage is detected on the specified (+) or (-) signal circuit
DTC B1025 02, B1035 02, B1045 02, B1065 02, B1075 02, B1085 02
A short to ground is detected on the specified (+) or (-) signal circuit
DTC B1025 04, B1035 04, B1045 04, B1065 04, B1075 04, B1085 04
An open is detected on the specified (+) or (-) signal circuit
Action Taken When the DTC Sets
The amplifier mutes the output channel and no sound is present from the speaker(s) that have a current circuit fault.
Conditions for Clearing the DTC
* The condition for setting the DTC is no longer present.
* A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.
Reference Information
Schematic Reference
Radio/Navigation System Schematics Radio/Navigation System Schematics
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
EL-50334-50 - USB Cable and Adapter Kit
Circuit/System Verification
1. Ignition ON, infotainment system ON, mute OFF.
2. Verify clear audio is heard from each speaker, adjusting fade and balance controls to test each speaker individually.
• If audio is inoperative from one or more speakers, or the audio emitted is not clear
Refer to Circuit/System Testing.
• If clear audio is heard from all speakers
3. All OK.
Circuit/System Testing
Note: In the following tests, audio signal frequencies (Hz) will be tested. To prevent misdiagnosis, the door chime must be OFF during testing. Ensure the driver door latch is closed during testing.
1. Ignition OFF, disconnect the harness connector at the appropriate P19 speaker. Ignition ON, infotainment system ON, mute OFF.
2. Test for 5-7 V between the appropriate signal circuit terminals listed below and ground.
* door, tweeter, and center I/P speakers audio (-) circuit terminal 1
* door, tweeter, and Center I/P speakers audio (+) circuit terminal 2
* subwoofer audio (-) circuit terminal A
* subwoofer audio (+) circuit terminal B
• If less than 5 V
1. Ignition OFF, disconnect the X1 and X2 harness connectors at the T3 audio amplifier.
2. Test for infinite resistance between the signal circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the T3 audio amplifier.
• If greater than 7 V
1. Ignition OFF, disconnect the X1 and X2 harness connectors at the T3 audio amplifier. Ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the T3 audio amplifier.
• If between 5-7 V
3. Mute OFF, play track number three (50 Hz bass test tone) from the test CD.
4. Test for 49-51 Hz AC between the appropriate signal circuit terminals listed below and ground.
* door, tweeter, and center I/P speakers audio (-) circuit terminal 1
* door, tweeter, and Center I/P speakers audio (+) circuit terminal 2
* subwoofer audio (-) circuit terminal A
* subwoofer audio (+) circuit terminal B
• If not between 49-51 Hz AC
Replace the T3 audio amplifier.
• If between 49-51 Hz AC
5. Test or replace the P19 speaker.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Speaker Replacement Reference Speaker Replacement Reference
* Control Module References Control Module References for amplifier replacement, programming, and setup.