GM Service Manual Online
For 1990-2009 cars only

Diagnostic Fault Information

Important: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

Circuit/System Description

The radio generates the audible warning through the left speaker. The radio receives audible warning requests via GMLAN serial data from the instrument panel cluster (IPC) or the body control module (BCM).

Reference Information

Schematic Reference

    •  Instrument Cluster Schematics
    •  Audible Warnings Schematics
    •  Body Control System Schematics

Connector End View Reference

    •  Instrument Panel, Gages, and Console Connector End Views
    •  Computer/Integrating Systems Connector End Views
    •  Inline Harness Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Scan Tool Data List

Circuit/System Testing

Important: Before performing this diagnostics, make sure no indicator(s) are illuminated after the IPC performs a lamp test. If any indicators are illuminated after the bulb test, perform the indicator diagnostics before this diagnostics.

  1. Ignition ON, radio ON, adjust the radio balance and fade to the left front speaker.
  2. If the speaker does not operate properly, refer to Speakers Inoperative - One or More .
  3. Ignition ON, verify that the scan tool Key In Ignition Status parameter is Key In.
  4. If not Key In, test the signal circuit and ground for a short to voltage or an open/high resistance. If all circuits test normal, replace the ignition switch.

Repair Instructions

Important: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Ignition and Start Switch Replacement
    •  Control Module References for the radio replacement, setup, and programming.