Circuit/System Testing

Verify the OnStar® voice recognition is operating normally.
- If the OnStar® voice recognition is inoperative, refer to Voice Recognition Inoperative or Microphone Inoperative - Caller Cannot Be Heard .
- Disconnect the radio harness connector. While holding the voice recognition button down, measure for 600Ω to 800Ω across the steering wheel control signal terminal (11) and the steering wheel control supply voltage terminal (10).
- If ohms are below or above the specified value, replace the steering wheel voice recognition switch.
Test the audio mic in circuits for an open, short to ground or a short to power. If all circuits test normal replace the radio.