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 CircuitDTC B1035 01: Audio Output 2 Right Front Circuit
DTC B1045 01: Audio Output 3 Left Rear Circuit
DTC B1055 01: Audio Output 4 Right Rear Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Left Front Speaker Output (+)/Left Front Low Level Audio Signal (+) | B1025 | 1 | B1025 | -- |
Left Front Speaker Output (-)/Left Front Low Level Audio Signal (-) | B1025 | 1 | B1025 | -- |
Right Front Speaker Output (+)/Right Front Low Level Audio Signal (+) | B1035 | 1 | B1035 | -- |
Right Front Speaker Output (-)/Right Front Low Level Audio Signal (-) | B1035 | 1 | B1035 | -- |
Left Rear Speaker Output (+)/Left Rear Low Level Audio Signal (+) | B1045 | 1 | B1045 | -- |
Left Rear Speaker Output (-)/Left Rear Low Level Audio Signal (-)Rear Low Level Audio Signal (+) | B1045 | 1 | B1045 | -- |
Right Rear Speaker Output (+)/Right Rear Low Level Audio Signal (+) | B1055 | 1 | B1055 | -- |
Right Rear Speaker Output (-)/Right Rear Low Level Audio Signal (-) | B1055 | 1 | B1055 | -- |
1. No or reduced sound from speaker | ||||
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.
Conditions for Running the DTC
The radio is ON.
Conditions for Setting the DTC
A short to voltage or 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
Entertainment/Communication Connector End Views
Description and Operation
Radio/Audio System Description and Operation
Electrical Information Reference
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 the signal circuit terminal A and ground.
- Test for 5.0-7.5 volts between the signal circuit 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. |
| ⇒ | 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 C2 and C3 harness connectors at the amplifier.
- Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.
- 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 all circuits test normal, replace the amplifier.
| • | Left front low level audio signal (+) - terminal B10 C1 |
| • | Left front low level audio signal (-) terminal B9 C1 |
| • | Right front low level audio signal (+) - terminal B8 C1 |
| • | Right front low level audio signal (-) - terminal B7 C1 |
| • | Left rear low level audio signal (+) - terminal B6 C1 |
| • | Left rear low level audio signal (-) - terminal B5 C1 |
| • | Right rear low level audio signal (+) - terminal B4 C1 |
| • | Right rear low level audio signal (-) - terminal B3 C1 |
| ⇒ | 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 |
