One or more heater & AC (HVAC) temperature and/or air delivery mode door actuator may fail, resulting in improper temperature or air delivery. If this occurs, fault code(s) should be stored in the HVAC control module which should assist in diagnoses.
Improper HVAC Temperature and/or Air Delivery Due to Failed Mode Door Actuator on GMC 2500 Pickup
Average mileage: 215,675 (180,000–251,350)
13 people reported this problem
1995 GMC 2500 Pickup 251,350 mi, Visitor
Heater never does what i want it to.
1997 GMC 2500 Pickup 180,000 mi, Visitor
left side of defrost vent is always in the open position