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

[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]

Access???

So I've narrowed it down to both the L&R and recirc actuators (See attached #1 and #2) 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....