I have been having a problem of Hot Air blowing out of the passenger front vents when the A/C is turned on. If I would switch to the heat setting, and then go back to cold setting, heat would still blow out of the vents even tho I could hear compressor working. Have had this problem for a year now, and asked on this forum but nobody new the answer, n some people had same problem, so thought I would help anybody out who may have this problem.
Well I flushed my radiator today and had to turn the heat on high to flush and fill radiator. When I turned the switch back to cold and turned A/C on, still hot air was blowing out of vents. It is way too hot in Arizona to not have Airconditioning!!! So I finally figured out what was the problem and here it is.
It is a faulty Air Mix actuator or Blend door actuator.
It is located on the passenger side floor board under the dash.If you have the hush panel it will need to be removed using 7mm socket.
Next you will disconnect the wiring harness and remove the two 5.5mm screw heads.
![DSC02404.jpg DSC02404.jpg](https://www.tahoeyukonforum.com/data/attachments/168/168065-cecf8d7a4564e32f95be648ea98ec72d.jpg)
After both screw are removed, the rear one is alittle difficult to get to so I just used the socket itself. The actuator itself should just pull right down, may be alittle tricky if fully in stop position.
I purchased a new actuator, and just reinstalled back into vehicle. You will want to make sure the door is positioned the same as the actuator by moving the arm in the vehicle, NOT THE ACTUATOR. DON'T ADJUST ACTUATOR ITSELF, LEAVE THE WAY YOU PURCHASED. Mine was set in the cold.
If you buy a new actuator, you need to make sure the part numbers match because they make many different styles of of these actuators for different vehicles and climate controls. Mine may differ from yours so don't base my part number on what you need to buy.
Now here is the tricky part that I had to research. Thanks to a site called Sparky's Answers, I was able to figure this all out and pass it onto everyone here. Very good information recieved, and very thurough. So I am going to use some of his information so everyone will be informed correctly.
Now supposedly if you have a scan tool you can adjust and calibrate the actuator thru the scan tool. Since I don't, he also gave information on how to calibrate without a scan tool. So here ya go.
First once you get actuator, new or used, make sure it can not move( I mean the metal know shouldn't be able to move by hand and diffenently don't move with pliers), if so, it is probably bad, if not go ahead and install the way it comes, and reconnect wiring. Then you will disconnect the battery for atleast 30 seconds. Then reconnect battery, turn the ignition to the ON position for atleast 1 minute, but he suggested 3-4 minutes so that's what I did, and DO NOT TOUCH THE A/C CONTROLS!!! You will then turn ignition to the OFF position for atleast 10 seconds, then start the engine and confirm the new actuator is working correctly by turning the climate knob from cold to hot. If all was done correctly it will work!! I checked the actuator by being on the passenger side, turning ignition on, moving climate knob, and sticking my head under dash to watch for the actuator to move.
SUCCESS!!! Hope this write up helps anybody with this same problem. Any questions please feel free to ask, and I will do my best to help. If I missed anything, or miss typed, very sorry, my kid is trying to help write this!! LOL