Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2008 GMC Yukon XL, 2008 GMC Yukon, 2008 Chevrolet Tahoe, 2008 Chevrolet Suburban, and 2008 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
Noise compensated volume only available on vehicles equipped with Y91 or UQS.
- Turn the ignition ON. Disconnect the noise compensation microphone.
- Measure for 7-9 volts between the noise compensation microphone supply circuit terminal A and the drain circuit terminal B.
- If the voltage is less than the specified range, test the circuits for a short to ground, or an open/high resistance. If the circuit tests normal, replace the auido amplifier.
- If the voltage is greater than the specified range, test the circuits for a short to voltage. If the circuit tests normal, replace the audio amplifier.
- If all circuits test normal, replace the noise compensation microphone.