How to fix Hot Air when A/C is on. Install new air mix/blend door actuator

[WHITEOUT]

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.http://i263.photobucket.com/albums/ii158/anjudoknow420/Photo2464.jpg

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.http://i263.photobucket.com/albums/ii158/anjudoknow420/DSC02409.jpg

Next you will disconnect the wiring harness and remove the two 5.5mm screw heads.http://i263.photobucket.com/albums/ii158/anjudoknow420/Photo2463.jpg
http://i263.photobucket.com/albums/ii158/anjudoknow420/Photo2469.jpg
http://i263.photobucket.com/albums/ii158/anjudoknow420/DSC02404.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.http://i263.photobucket.com/albums/ii158/anjudoknow420/DSC02402-1.jpg

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.http://i263.photobucket.com/albums/ii158/anjudoknow420/DSC02402.jpg

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

[oak510_tahoe]

great info, thanks for sharing.

[WHITEOUT]

I hope it helps people who had this same problem, I know I have asked about this before with nobody having a clue how to fix. Atleast at the time I asked, maybe this has already been brought up, just giving a how-to helper. Probably shoulda put in the tech forum tho, my bad if misplaced.

[Riff Raff]

Nice write up

[Modded]

Nice write up, hopefully I never need it haha.

[Stockfornow]

Very nice write up. I need to check out the actuator for my rear vents as I only get "cool" air, not hot.

[Redhoe01]

Dude, you are the man, this problem always pissed me off.

[WHITEOUT]

Ya, I remeber awhile back asking about this, and others asking as well how to fix this problem, and nobody knowing, so I had to get mine taken care of the other day in the 110degree Az heat!!! So it should be useful to anybody who has this same problem.

[flyinghigh54]

I have that problem with my rear ac, i just got the new actuator think ill do a write up on it.

[Stockfornow]

I have that problem with my rear ac, i just got the new actuator think ill do a write up on it.

Please let me know when you do the write up as I need to mess with the rear AC as well!

[SFBerto415]

?How much do the actuators cost? And where should I purchase from?

[amaz]

I have the same problem in my tahoe, but now that the actuator is stuck in cold -position, I haven't got any intrest to fix it, maybe when it's gettin colder and I need to get some hot air into the truck.

[Boomer73]

Very nice. Thanks for the excellent post.

-B

[ballsie]

i have this problem on my driver side about everty 2 months. the actuators are $265 at the dealer and $35 on ebay! looks like I have some directions now! Thanks!!

[Narco]

AWESOME post bro! ill move it to the tech section. any of you other guys that do this should take pics also and add to this.

Whiteout - what did you pay for your part and where did you get it?

[Tahoewhat]

I know this a old thread, but its a very helpful thread, thanks whiteout, should definently be a sticky.
But my a/c just stopped working, bad blower motor, replaced w/ new blower motor. But its not blowing hard like it should. I got it once to push air like i used to, even w/ the recirc. air on, but now its just barley even blowing air. Is this the actuator going bad also? Should i go ahead install the actuator also and then disconnect battery like stated to have it all work properly? Also, i have the digital climate control.

[smurphy80]

Does this also apply to an '02 yukon with electronic climate control? I have the hot air issue from time to time when I first start my truck and it idles for a few minutes or I pull over and it idles for a few minutes, hot air starts to come out of the vents. But as soon as I start driving it cools right down again. Any ideas?

[scorpio]

I have that problem with my rear ac, i just got the new actuator think ill do a write up on it.

+1 same problem here but i had went to the junkyard got 3 actuators for the back and as soon as i conect them and turn on the heat they still go to the same position and only cold air comes out. Plz let us know what come up with. Thanx

[jmyler]

This is why i come to forums. Great man!

[ilmk123]

smurphy80 I had this same problem and my system was over charged. When sitting idling the pressure would build up and sometimes it would even kick off the compresor.
The shop pulled it down and recharged it. The air is cold but only in the back. It blows only cool air out both sides of the front vents. I have disconnected the actuator above the hump and move it by hand and it would get no colder. So I am still tryin g to figure thie out......Scott

[Tahoewhat]

Well figured mine out, my a/c stopped blowing. No force, so i tried the blower motor, wasnt that as i found out, changed out auto climate, wasnt that, so then changed the blower resistor, connected to the blower and now i have full force a/c.. In my mind, it works better than before.. So i say change your blower resistor if any problems.

[Cheddar]

I have an 02 with the same issue, Whiteout, what year is your Tahoe? and where did you order the part from ? Nice write up !!!

[bfranklin74]

hello, thanks for the post. I have an 05 tahoe with the same problem as first stated. It blows cold on drivers side and about 300 degrees on passenger. I went and bought a brand new actuator today and followed the directions to a t now i still have the same problem. What do i do now??

[Clemsonbloz]

the blend door act for the other side is behind the radio! That was the easy one to get to.. There is also one on the drivers side above the hump that controls the air location(defrost,floor,vent, ect)..

Word of advice.. The back bolt in the long panel that he removed to get to the blend door act,,the aggervating one over the hump,,, throw it away.. the other fasteners will hold everything just fine, and you'll never deal with that aggervating bastard-bolt again!

[bfranklin74]

LMAO. bastard is one of the very few words i called that bolt. lol thats funny. Anyway today I figured out the problem. It was the actuator under the dash pad to the right of the radio. Now your taking some curse words. That was a JOB!!! took me about 2 hours but now im blowing COOOLLLLDDDD.. I think I did pretty good I only had 2 screws left over!! Not BAD! But I would suggest letting a mechanic do it!

[gringoloco]

Thanks for this. Took me forever to finger out what was going on with mine. One of those things you don't think about 'til you're sitting at a stoplight and your dash starts chucking fireballs...

[garcia2002]

Thanks for the write up...

[WHITEOUT]

Hey everyone, so sorry about not replying, kinda forgot about this thread, since when I wrote it, no one seemed to care at the time!!! LOL. I know alot of people had this same problem, so... I'm back to help if I can.

I went to the junk yard personally, cause I wasn't about to pay the $75-$150 they want for these actuators brand new!! But that's me, and I picked up an extra one incase. Paid $20 total for 2. I have an 01' Tahoe, so everyone who is looking to do this needs to check the numbers on the back, or bottom of there actuator to ensure they are getting the right part. Seemed like different years, makes, models, had different actuators. So, make sure you get the right one.

Bfranklin74- yours sounds like the actuator behind the dash, cause your atleast blowing cold from one side, but not the other. And pretty sure that actuator behind radio controls left and right/driver/passenger, air. But didn't need to mess with that personally

As far as rear air goes. Mine was blowing cold in rear, but hot in front if I moved control knob. Rear always worked for me, so never had to mess with it.

Sorry again guys about not responding to my own thread!!!:emotions122:
Here to try and help now if I can.

Owe, and make sure to follow those re-learn steps!!! Actuator needs to be recalibrated to your system and how it is set.

[twbauer]

Just went through the blend door actuator mess and how it was fixed. I wrote up how I cleaned my actuator and got it working again. Thread is in the general section of the forum. Title is "blend door actuator or climate control".

[florida boy]

Anyone know which actuator would cause hot air on the drivers side only? This has been happening about every 3 days now and want to get it fixed. Thanks.

[WHITEOUT]

I believe it's the actuator that is behind the radio, or possibly right under drivers dash. think that's the one that controls the air from left and right in front. someone else might know exactly, but I believe it's that one. Best way to figure it out, is get in there, move the door manually to see if it fixes the problem.

[wrx600rr]

could this be my problem only opposite? I have my heat on and only cold air comes out, the rear has heat but not the front so I know its not my heater core and its not leaking water anywhere in the cabin!

[Clemsonbloz]

the blend door actuator behind the radio does the passenger side.. driver side is above the hump...

I had the drivers side hot last summer,, took the actuator out, and apart and cleaned.. works like a champ..

the passenger side now is being dumb, and it's the bastard part behind the radio...

[endo]

Thanks for the write-up, just fixed mine on a GMC Sierra.

[LaOrange]

Hi all
I have the same problem on all three Front Driver, Front Passenger, and Rear
at times They will work for months at a time Then drive you NUTS
If i turn the Truck off and restart it usually works again
I guess I will have to change ALL 3
Thanks

[Ced]

cosign with LaOrange

[ScottyBoy]

Mine has been acting up for damn near 3 years now. But I learned how to deal with it. The actuator will only get stuck if I turn it all the way to hot. As long as I don't turn it 100% to the right for complete hot then it will go right back to cold. If it ever gets permanantly stuck then I will definitely replace the actuator. LOL!

[LiftedTahoe847]

man i gottta 97 thats kinda doing the opposite. I have very little heat when cranked up to hot. No rear controls on my hoe but my thermostat, waterpump, radiatior is all new. Both hoses to heater core are hot to the touch so thats fine too. SOMEONE PLEASE help me here. cold as hell here in chicago and my mf heats acting up.

[viperbluelx]

Is that one considered the "main" actuator, or the "auxiliary" actuator? Mine is bad also but the parts store lists two, one's around $40 and the other is around $140.

[dubyatf]

My '04 Tahoe with climate control needed a blend door actuator. Symptoms were: Intermittent hot air with A/C on - usually it would stay hot. At first, as others have experienced, turning off ignition and restarting vehicle would correct. Even that trick eventually just stopped working however. When the hot aired flowed the blower would speed up too - when in the automatic mode.

GM part number was 89018365. I paid about $150 for it - I'm sure you can get it cheaper in Dorman or at thru an AC/Delco Distributor.

[viperbluelx]

My '04 Tahoe with climate control needed a blend door actuator. Symptoms were: Intermittent hot air with A/C on - usually it would stay hot. At first, as others have experienced, turning off ignition and restarting vehicle would correct. Even that trick eventually just stopped working however. When the hot aired flowed the blower would speed up too - when in the automatic mode.

GM part number was 89018365. I paid about $150 for it - I'm sure you can get it cheaper in Dorman or at thru an AC/Delco Distributor.

Which specific actuator did you change? The easy one near the center console.

[dubyatf]

Which specific actuator did you change? The easy one near the center console.

Actually, I had somebody install it. Judging from what I was charged and how long it took to R&R - I'd say it was the easy one to change.

[Edit: I'll add to my symptoms in case it might help others troubleshoot... Both the left and right front vents had the same issues though I can't remember if the defrost worked as it should. The rear A/C worked fine however.]

[Darthkim]

Dudes, for the life of me i don't understand where the blend door actuator IS on the 2004 GMC Yukon.

My symptom is that the driver side is hot, while the rest of the AC is fine.

I understand that I should change the left side actuator, but earlier today I replaced what I now know as the mode actuator.

Can someone tell me where this part is (in layman terms? )

[o'doyle]

Having the same issues with the wife's 05 Tahoe.. Drivers side will get hot while everything else is nice and cool. Turning the ignition off and back on is working for now but from the sounds of it that isn't a permanent fix ..

Sounds like the actuator near the center is to blame

[ktmhans]

So reading threw this thread i think i have a good handle on whats wrong with mine. Also posters should be read the whole thread and get there answers. Theyve been answered. But what im wondering , is there a test method to see if these little buggers are working. Can you just have the truck running, crank the knob and watch it move? All the different ones.
I not only have the heat problem my blower sometimes doesnt blow hard, like 50% i would say. Then you play around with climate control and boom it rams up and blows hard. I saw maybe a blower risistor? Any help on that one.

[balexander26]

But what im wondering , is there a test method to see if these little buggers are working. Can you just have the truck running, crank the knob and watch it move? All the different ones.


I don't think this is a good idea. I have done this exact thing to test if one of mine were working. It appears that the motor actually has a sensor that stops the motor when it feels resistance...and if it's not connected to the vehicle it will not feel resistance therefore it will turn too far.

So now I have this actuator off the vehicle and cannot reinstall it because the motor has turned the shaft too far...anyone know how to recalibrate it so it can fit back onto the vehicle?

[pjtoy2]

OK i did read through this whole thread and I'm not sure if I missed it but I cant find the location of the rear actuator...

[balexander26]

OK i did read through this whole thread and I'm not sure if I missed it but I cant find the location of the rear actuator...

This might help you: http://www.tahoeyukonforum.com/forum/showthread.php?t=12635

---------- Post added at 06:12 PM ---------- Previous post was at 05:38 PM ----------

So now I have this actuator off the vehicle and cannot reinstall it because the motor has turned the shaft too far...anyone know how to recalibrate it so it can fit back onto the vehicle?

Just in case anyone wants to know the answer to this. Took out the actuator P/N 52402588 and opened it up. All the gears were in good shape but there are 2 phosphor bronze semicircular wipers under the final gear which I believe send the feedback signal. Cleaned both, bent the wipers a little more and lightly relubed the gears. Set the actuator in mid position along with the door. (just barely reach it as it protrudes almost to the right side of the floor hump) re installed it and it has been functioning correctly.

Still having cold air coming out my passenger side when the heat is on so it's looking like I'm going to have to remove the dash to replace that top actuator.

Anyone know if it can be reached through the glove box?

[Fordbeater]

In addition to faulty actuator motors, the blend door itself can also be broken. This happened on my Tahoe. Typically it is a very labor intensive and costly fix to replace a broken blend door, as the dash must be removed and the plenum assembly replaced. There is a DIY kit from heatertreater.net that provides steel hardware as well as instructions on how to perform the repair by removing the glove box rather than the entire dash.

This is also an alternative to replacing the 'difficult to access' top actuator motor underneath the dash. The kit contains a single blend door which converts the dual control to single control, and is operated off of the bottom actuator motor, which can be accessed by removing the glovebox. If you are having issues with your blend door, or the 'top blend door actuator motor behind the dash' it is worth looking into.

[DoABurnout]

So I've narrowed it down to both the L&R and recirc actuators (See attached #1 and #2) 15334 My question:are these actually doable without removing the whole HVAC Module? I started to dig into it and it doesn't look like much fun....