Automatic Climate Control -- Out of Whack --

[WingsAA]

Okay, I've searched a bit but the heat up here is getting to me

It seems my automatic climate control has developed a mind of it's own. Shortly after starting the burb... it switches the air blowing from the dash vents to the floor and then quickly switches to having the air only coming out of the defrost vents. I haven't checked to see if the rear air is operating properly but will report back once I confirm.

Anybody dealt with this on the GMT900's yet?

 

[Fishmazter]

I have a 2008 Tahoe LTZ and it's doing the exact same thing. Used to be very infrequent but now it happens almost every day - especially when it gets warm outside. Also just started blowing hot air on some occasions when it is hot. Hopefully someone on here knows what is going on!!!

 

[Goodinblack]

I had mine taken in for blowing hot on the left side, cold on the right. They "reprogrammed" the actuators is what the service rep told me. It was done under CPO warranty. Has not done it since.

 

[WingsAA]

I could hear a ticking... like a clock behind the dash about a month ago that would occur randomly. I just thought it was a bomb and my burb was going to blow. Okay, just kidding but I really didn't know what it was. Now that this has occurred, I'm guessing that it's related.
Another update, it stopped doing this last night for now and the air is blowing consistently out of the vents however, it's surging now..nothing major... Can hear it increasing and decreasing the speed.

I'll have to call the dealer and check but I'm hoping it's something simple like reprogramming.

 

[LTLux]

It sounds like one of your actuators is going bad. Not a hard fix if not under warranty. Just do some searches for actuators and you will see. Sounds like blend door actuator to me.

Also, if you just got a new AC head unit that does have to be programmed at the dealer or it will not work right, trust me, I know!

 

[WingsAA]

It sounds like one of your actuators is going bad. Not a hard fix if not under warranty. Just do some searches for actuators and you will see. Sounds like blend door actuator to me.

Also, if you just got a new AC head unit that does have to be programmed at the dealer or it will not work right, trust me, I know!

Thanks! I'll do some searches later and see what I find. It would be great to be able to tackle this myself.

 

[WingsAA]

Well, I think this is the cluprit...

I'm going to tackle it myself just need to determine where to get it from seems like there is a modest difference in prices. Not sure if there is a quality difference.

HVAC Door actuators

 

[Fishmazter]

How did you track it down to that part number? I wonder if it is the same part number for the Tahoe. Mine is out of warranty so a DIY fix sounds good.

 

[Goodinblack]

That diagram show a Expedition.

 

[WingsAA]

That diagram show a Expedition.

Apparently they changed the links to the pictures cause they were right.

As for the part numbers, I have a subscription to alldatadiy and pulled the information from there. It had all the pics and technical details.

 

[Goodinblack]

Cool.....Report back at 0900 LOL.....Let us know how it goes. We may be there one day too.

 

[WingsAA]

Cool.....Report back at 0900 LOL.....Let us know how it goes. We may be there one day too.

Roger that.

Part should be delivered in the next couple days. I'll do a diy and post up when it's done.

 

[RoliO]

Roger that.

Part should be delivered in the next couple days. I'll do a diy and post up when it's done.

How much was the part? And what is the correct p/n? Just in case I need it sometime.

 

[WingsAA]

How much was the part? And what is the correct p/n? Just in case I need it sometime.

Part was 64.99 from AAutoznfora Dorman part. I cross-referenced it against the dorman website. There are three that can work but from reading the descriptions I'm sure this is the one. Guess I'll find out when I get in there and confirm.

http://www.autozone.com/autozone/pa...gzxZ9pelb?itemIdentifier=994167_361647_18453_

 

[WingsAA]

Okay... Works all done. Was actually pretty easy and took about 30 min. I'll get the pics up soon.

 

[WingsAA]

Okay, here goes my crappy attempt at a DIY...

Remove the side panel and knee bolster. The side panel is a pull off (easy). The knee bolster is not difficult, just remove the two screw on the bottom and one bolt behind the parking brake pull (It holds the parking brake release. Once you remove the bolt just swing the cable and latch out of the way...

To get the knee bolster off just pull firmly and it will release the metal clips from the sockets.

Now remove the floor vent duct. There is one plastic push pin that you remove towards the driver side (circled in red). Once that's removed just pull it off.

You will be able to see the actuator held in place with two small bolt/screws and the small electrical connector. Simply disconnect the connector and remove the two bolt/screws and then pull straight back while managing to push with you other hand to hold the gears keeping them from pulling out as well. This is where it helps to have smaller hands. I still cut the hell out of my left hand...

One note... When you put back on the new unit, you'll have to move the gear so that it centers back into the actuator groove... you'll understand when you see it.

!!!This part is important!!!

When you connect the electrical harness and are all ready to go... before putting everything back together, turn the ignition on but don't start the truck. Power on the climate control unit and let it sit. If you stick your head under and watch, you'll see the actuator cycle through and re-sync... it needs to do this or you'll be going to the dealer. Shouldn't take more than 30 seconds.

Following this, you can cycle through the modes (Vent/Blend/Floor/Defrost-Floor/Defrost) and watch the actuator move the gears/door. If you did it correctly.... you'll see everything meshing and understand how the system operates.

---------- Post added at 09:45 PM ---------- Previous post was at 09:41 PM ----------

Here's the unit with the new one on the left:

And here is the old part disassembled. It appeared to be functioning but something was clearly not working with it.

If you're in or near Columbus and need this done... I'd be glad to help out as it's pretty easy.

 

[LTLux]

Great write up!

Glad I could point you in the right direction.

 

[WingsAA]

Great write up!

Glad I could point you in the right direction.

Me too... thanks brotha!

 

[Goodinblack]

Thanks, may be necessary someday. I wondered where those things hid.

Great pics.

Maybe a sticky in technical?

 

[Fishmazter]

Awesome DIY write up. Just installed mine in less than 30 min. Instead of Dorman part I purchased an AC Delco part ( identical to the GM part) from Amazon for $36 delivered. It also included the main gear but I didn't use it. So far it is working great.

Part # is 15-73952. (direct fit for GM 89018374)