PRE-RELEASE
OnStar Audio Malfunction
| OnStar Audio Malfunction |
| Diagnostic Instructions |
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Perform the
Diagnostic System Check - Vehicle
prior to using this diagnostic procedure.
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Review
Strategy Based Diagnosis
for an overview of the diagnostic approach.
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Diagnostic Procedure Instructions
provides an overview of each diagnostic category.
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| Diagnostic Fault Information |
| Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
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Audio Signal
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1
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1
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1
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Audio Common Signal
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1
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-
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1. No (or Noisy) OnStar® Audio
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| Circuit/System Description |
When an OnStar® key is pressed, a serial data message is sent to the audio system to mute all radio functions and output OnStar® originated audio. After the audio system is muted, the telematics communication interface control module transmits signals to the audio system on the audio signal and audio common circuits.
| Reference Information |
Schematic Reference
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OnStar Schematics
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Radio/Navigation System Schematics
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Connector End View Reference
Component Connector End Views
Description and Operation
OnStar Description and Operation
Electrical Information Reference
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Circuit Testing
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Connector Repairs
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Testing for Intermittent Conditions and Poor Connections
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Wiring Repairs
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Scan Tool Reference
Control Module References for scan tool information
| Circuit/System Verification |
| 1. |
Tune radio to a known good station and verify the audio is heard clearly through all speaker channels.
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| 2. |
If audio is not heard clearly, refer to
Speaker Malfunction
.
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| 3. |
Ignition ON, radio ON, set volume to comfortable level and press OnStar® Call Center button. Verify Connecting to OnStar® message is heard clearly through the audio system.
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| 4. |
If OnStar® message is noisy or distorted, refer to Circuit/System Testing.
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| Circuit/System Testing |
| 1. |
Ignition OFF, disconnect the X1 harness connector at the radio.
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| 2. |
Ignition ON, test for a varying AC voltage between the following signal circuit terminals listed below and ground when the OnStar® Call Center button is pressed.
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Audio Signal Circuit - terminal 20
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Audio Common Circuit - terminal 6
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| 3. |
If AC voltage was not present, test the circuit for a short to voltage, short to ground, or an open/high resistance. If the circuit tests normal, replace the K73 telematics communication interface control module.
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| 4. |
If all circuits test normal, replace the radio.
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| Repair Instructions |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for radio or telematics communication interface control module replacement, setup, and programming.
