Do you hear a ticking noise from your dash when the ignition key is on? Does your car heater blow cold or the air conditioner blow hot? These are signs that a blend door actuator has gone bad.
Link to order a Door Actuator: https://amzn.to/2tRB5UP
About a half hour of your time you can replace this part to get your climate control back working again. Or you can see what you are paying for when taking your car in for repairs.
2007 Hummer H3
WHAT GOES WRONG?
A blend door actuator is made up of an electric motor that turns a plastic gear set in one direction or another which is connected to an air control door pivot at the final drive of the unit. An actuator can go bad in of two ways; first the electric motor can burn out rendering the unit non-responsive so nothing changes when the temperature or vent mode controls are moved. Next, the plastic gear set will become brittle and break which will sometimes allow the unit to work while making a ticking or clicking noise and then stop. This is a common problem in most car’s heater and air conditioner systems.
HOW DOES IT WORK?
An air blend door actuator is constructed from a plastic housing, a small electric motor and a plastic gear set. A door position sensor is also incorporate into the unit to send feed back information to the climate control computer.
This actuator then moves temperature and air direction doors inside the heater plenum (box) which are designed to control mode settings such as temperature, floor, mid vent, defrost and fresh air or re-circulation modes. They also control hot and cold settings for right and left passenger compartments.
Your car’s climate control computer gives an electrical command to the actuator to start moving the actuator motor to change air direction modes. This direction is according to the temperature chosen by the driver or passenger on dual climate control systems.
Most systems have three to four of these units placed in various areas around the HVAC plenum that control mode operation and will vary by the car make and model.
See HUMMER H3 Playlist for more; https://www.youtube.com/watch?v=Rqxx0u39vWc&list=PLKE7F0aRK-jk09r9uHQt8shgiHB-d7MO_
See RV TRIPS Playlist for more;