GM Service Manual Online
For 1990-2009 cars only

Begin the system diagnosis with the HVAC Blower Controls Circuit Description , HVAC Air Delivery/Temperature Control Circuit Description or HVAC Compressor Controls Circuit Description .

Reviewing the Description and Operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the Description and Operation information will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms .