New blend door actuater..."not working" '05 Tahoe

My dad has had problems with the Driver’s side A/C in his '05 Tahoe. It only blows hot.

He just had the evaporator core and heat core replace. They added the blend door actuator that was missing (from a Midas “replacement” job), and it worked for a day or so, and now hot air only.

The mode (defrost, floor, head) function works, the passenger side temp blend works, but the drivers temp does not. As mentioned above, the actuator has been replaced a couple of time and every time the temp works a few days and then heat only.

Is there some kind of temp sensor that needs to be replace?

Any other ideas?

Yes, find yourself a better mechanic. There is more than one of these actuators, how many depends on the system installed in your vehicle.

Clearly Midas is not getting the job done nor is the second shop. This suggestion is based on the limited info you provided plus I am assuming neither you nor dad actually work on your own cars.

Look for a well rated independent shop… not a chain like Midas, Pep Boys or Les Schwab.


You assumption isn’t completely accurate, but with the information at hand, logical.

I do work on vehicles, but am not an anywhere close to an expert on the mater. That is why I really like and appreciate the Car Talk forum…there is a lot of good info here.

I kept telling my dad stop using Midas, but he’s a grown man and can make his own mistakes. LOL

The second shop…it was their first time touching the vehicle and they come highly recommended in the area. I am also not sure they knew all of the history of the vehicle.

That being said, I really do appreciate the input, but the question at hand still stands…

Is there some kind of temp sensor that needs to be replace?

Any other ideas?

I am asking because I don’t know AC that well, but I would like to take a crack at it now for a lot cheaper than paying a shop.

Some times you can pull the fuse for the climate control to reset the system and it will go back to functioning normally. Search “2005 Silverado climate control reset” for the procedure (Silverado and Tahoe will be the same). I had to do it once on my Sierra after installing a new climate control unit. There are a few steps you have to go through with turning the key to on for a certain period and then turning it back off after you reinstall the fuse, but I don’t remember the exact procedure. There’s a site called “Sparky’s Answers” that has some pretty good info on the climate control system and I believe this procedure is listed there also.

If the Tahoe has the automatic climate control, I’m going to be in over my head. Mine has the manual dual climate control and I’m more familiar with that system. If the reset doesn’t help, and the correct new blend door actuator was installed, I can’t think of many other things that would fail other than the climate control module itself (the controller “head unit” with the buttons and dials) on the manual system, at least. I’m not sure if the auto climate control has other components. I would definitely check out that “Sparky’s Answers” site. Goofy name, but he seems to be pretty knowledgeable. I don’t have any affiliation with Mr. Sparky, btw.

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There may be a problem in HVAC control module.



Yes, several different kinds… here

This video supposedly shows you how to replace one… didn’t watch it, I don’t need to replace one…

But you still haven’t told me what system your dad’s truck has…

Ok, sorry, it has a dual control digital disply system like shown by Tester.

Thank you for you information. I have the “digital” dual zone temp control.
I was just reading about the reset a little bit ago. I am going to try that tonight when I get home as a “step 1” of diagnosing.

I don’t think it will help, but its quick and easy, and requires no parts.

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Just watch the video. Thank you for that I really appreciate it, but it is for newer model trucks.