• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Amplifier Battery Positive Voltage | 1 | 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 Signal (+) | B1065 02* | B1065 04* | B1065 01* | -- |
Front Center Speaker Signal (-) | B1065 02* | B1065 04* | B1065 01* | -- |
Subwoofer Audio Signal (+) | B1075 02* | B1075 04* | B1075 01* | -- |
Subwoofer Audio Signal (-) | B1075 02* | B1075 04* | B1075 01* | -- |
Amplifier Ground | -- | 1 | -- | -- |
1. Amplifier inoperative/no sound from speakers * Speaker output DTCs available when equipped with amplifier UQA only |
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 approCimately 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.
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.
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.
• | 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. |
The radio is ON.
A short to voltage is detected on the specified (+) or (-) signal circuit
A short to ground is detected on the specified (+) or (-) signal circuit
An open is detected on the specified (+) or (-) signal circuit
The radio disables audio output on the appropriate channel
• | The condition responsible for setting the DTC no longer eCists. |
• | A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred. |
Radio/Navigation System Schematics
Entertainment/Communication Connector End Views
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.
• | 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. |
• | Subwoofer speaker output (+)- terminal 1 C1 |
• | Subwoofer speaker output (-) -terminal 2 C1 |
• | Left front speaker output (+)- terminal 4 C2 |
• | Left front speaker output (-)-terminal 5 C2 |
• | Right front speaker output (+)- terminal 7 C2 |
• | Right front speaker output (-) -terminal 6 C2 |
• | Left rear speaker output (+) -terminal 15 C2 |
• | Left rear speaker output (-) -terminal 14 C2 |
• | Right rear speaker output (+)- terminal 16 C2 |
• | Right rear speaker output (-)- terminal 8 C2 |
• | Front center speaker output (+) -terminal 13 C2 |
• | Front center speaker output (-)-terminal 12 C2 |
⇒ | If greater than the specified range, test both signal circuits of the affected speaker for a short to voltage. |
• | Subwoofer speaker output (+)- terminal 1 C1 |
• | Subwoofer speaker output (-) -terminal 2 C1 |
• | Left front speaker output (+)- terminal 4 C2 |
• | Left front speaker output (-)-terminal 5 C2 |
• | Right front speaker output (+)- terminal 7 C2 |
• | Right front speaker output (-) -terminal 6 C2 |
• | Left rear speaker output (+) -terminal 15 C2 |
• | Left rear speaker output (-) -terminal 14 C2 |
• | Right rear speaker output (+)- terminal 16 C2 |
• | Right rear speaker output (-)- terminal 8 C2 |
• | Front center speaker output (+) -terminal 13 C2 |
• | Front center speaker output (-)-terminal 12 C2 |
⇒ | 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 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. |
⇒ | If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the audio 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. |
Perform the Diagnostic Repair Verification Diagnostic Repair Verification Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for radio or amplifier replacement, setup, and programming |