Silverado HVAC Blend Door Actuator Not Working

Scott Cadwell · April 18, 2020

ok, I tried the reset that was recommended and it worked, I was thrilled until the next time I used the truck the AC only blew cold for a few seconds then started blowing hot again, just like before......I assume it's a bad actuator and the "reset video" I watched said it was probably the one located by the heater vents nearest the floor near the hump.......any thoughts? how to test it, and or feedback if this info is correct?

UofAZCats · May 1, 2020

I had the same issue but it lasted longer then 3 seconds before blowing hot. It was random as heck and so I took a long time before I bit the bullet and had my mechanic fix it. The actuator is deep in behind the dash and requires taking the whole dash off. The part was something like $40 but the labor was what got you because getting to it was a long process. I think the total bill was something like $500-600. The amount of labor was what kept me from giving it a shot. Good luck with it.

dsr611 · May 1, 2020

Our 05 Tahoe is the same way...when it starts blowing hot, I just roll the windows down. I'm not about to get into tearing the dash out

Scott Cadwell · May 14, 2020

UPDATE: I fixed mine with an $11. part off ebay and it only took 5 minutes.......I don't know if there are other actuators that go bad that are "buried" behind the dash, but mine was the one the video mentioned, right near the transmission hump.......it's such a cheap part and easy replacement that it was worth the gamble and it paid off!!........Thanks utube, got no help here : (

DDAY · May 16, 2020

2007-2013 Blend Door is as simple as you stated. The previous generation, you had to take the dash out and is a longer process. I was very happy how easy it was to replace my 2013.

Scott Cadwell · May 19, 2020

Mine is a 2004 Silverado, so that is not accurate........perhaps that is what dishonest mechanics have lead people to believe???........or perhaps there are multiple blend doors and I just lucked out??

davester · May 19, 2020

I think it's the mode actuator that sucks to get at in the GMT800's. Two of actuators are relatively easy to get to, the third one is buried.

swathdiver · May 23, 2020

On 4/18/2020 at 4:04 PM, Scott Cadwell said:

ok, I tried the reset that was recommended and it worked, I was thrilled until the next time I used the truck the AC only blew cold for a few seconds then started blowing hot again, just like before......I assume it's a bad actuator and the "reset video" I watched said it was probably the one located by the heater vents nearest the floor near the hump.......any thoughts? how to test it, and or feedback if this info is correct?

Your system has 4 actuators if it is an automatic, dual zone system. You need to find someone with a bi-directional scan tool that can read BCM codes or get your own. A Tech-2 or a VXDIAG Nano with Tech2Win and a tablet can get the job done. This will tell you which actuator(s) are not working right and why. No more guessing and wasting money.

The actuator under the dash on the driver's side is for the modes. The actuator near the hump in the passenger footwell is for the driver's temperature control. Directly above, on top of the air box is the one for the passenger side. Next to that, mounted vertically, is the recirculate actuator. Trouble codes will identify which actuator failed and why, such as short to ground or it got stuck. The scan tool can also properly recalibrate the actuators.