Speaker Malfunction
Speaker Malfunction
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 provide an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The up-level radio (UQA) supplies 4 channels of audio to an amplifier. The amplifier supplies 6 input signal channels to 8 speakers.
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.
Diagnostic Aids
The front tweeter speakers are connected to the same channel as the front door speakers.
Circuit/System Verification
Radio ON, Rear Seat Audio (RSA) OFF(if equipped), 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 (UQ3)
1. Ignition OFF, disconnect the harness connector at the appropriate speaker.
2. Radio ON, test for 5.0-7.5 volts between the speaker circuit terminal A and ground.
• If greater than the specified range, test the speaker 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 speaker circuit terminal B and ground.
• If greater than the specified range, test the speaker circuit for a short to voltage. If the circuit tests normal, replace the radio.
• If less than the specified range, test the speaker circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the radio.
4. If the vehicle is equipped with UK6 Rear Seat Audio and the concern is with a rear speaker, Test the speaker circuits between the radio and the RSA control.
5. If all circuits test normal, test or replace the speaker.
With Amplifier (UQA/UQS)
1. Ignition OFF, disconnect the X1and X3 harness connectors at the amplifier.
2. Radio ON, Rear Seat Audio OFF, test for 5.0-7.5 volts between the appropriate speaker circuit terminal listed below and ground.
With UQA
* Left front speaker control- Connector X2, terminal 4
* Left front speaker control- Connector X2, terminal 3
* Right front speaker control - Connector X2, terminal 2
* Right front speaker control - Connector X2, terminal 1
* Front center speaker control - Connector X2, terminal 13 (w/ Y91)
* Front center speaker control - Connector X2, terminal 1 2(w/ Y91)
* Left subwoofer speaker control- Connector X1, terminal 7
* Left subwoofer speaker control- Connector X1, terminal 3
* Right subwoofer speaker control- Connector X1, terminal 2
* Right subwoofer speaker control- Connector X1, terminal 6
With UQS
* Left front speaker control- Connector X2, terminal 4
* Left front speaker control- Connector X2, terminal 5
* Right front speaker control - Connector X2, terminal 7
* Right front speaker control - Connector X2, terminal 8
* Front center speaker control - Connector X2, terminal 13 (w/ Y91)
* Front center speaker control - Connector X2, terminal 1 2(w/ Y91)
* Left subwoofer speaker control- Connector X1, terminal 1
* Left subwoofer speaker control- Connector X1, terminal 2
* Right subwoofer speaker control- Connector X1, terminal 3
* Right subwoofer speaker control- Connector X1, terminal 7
• 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. 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