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: Speaker Output Shorted to Ground or VoltageDiagnostic 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 (+) | B1025* | 1 | B1025* | -- |
Right Front Speaker Output (-)/Right Front Low Level Audio Signal (-) | B1025* | 1 | B1025* | -- |
Left Rear Speaker Output (+)/Left Rear Low Level Audio Signal (+) | B1025* | 1 | B1025* | -- |
Left Rear Speaker Output (-)/Left Rear Low Level Audio Signal (-) | B1025* | 1 | B1025* | -- |
Right Rear Speaker Output (+)/Right Rear Low Level Audio Signal (+) | B1025* | 1 | B1025* | -- |
Right Rear Speaker Output (-)/Right Rear Low Level Audio Signal (-) | B1025* | 1 | B1025* | -- |
1. No or reduced sound from speaker * Noticeable Distorted Audio Possible | ||||
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. 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.
Conditions for Running the DTC
The radio is ON.
Conditions for Setting the DTC
A short to voltage or a short to ground is detected on a speaker output signal circuit.
Action Taken When the DTC Sets
The radio disables its outputs on one or more channels, producing no sound.
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. All speakers should function properly.
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 C3 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 audio signal (+) - terminal 1 |
| • | Left front low audio signal (-) - terminal 2 |
| • | Right front low audio signal (+) - terminal 10 |
| • | Right front low audio signal (-) - terminal 9 |
| • | Left rear low audio signal (+) - terminal 4 |
| • | Left rear low audio signal (-) - terminal 3 |
| • | Right rear low audio signal (+) - terminal 11 |
| • | Right rear low audio signal (-) - terminal 12 |
| ⇒ | 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 |
