Just finished replacing the HVAC mode door actuator in my 2011 Grand Sport. The issue was that the motor constantly was clicking three to eight times and this would repeat itself about every 30 seconds to every couple of minutes. Very annoying! The GM dealers wanted $55-$62 for the actuator but I found it on amazon for $29 including shipping.

Here are the steps to replace this actuator; it isn't necessary to remove the dash.
1. Remove the glove box door. Open the door and remove the cable that lets the door open slowly. There is a plastic button that holds the cable to the side of the glove box. Simply slide the button downward and it will pop out of the side of the glove box. Each side of the glove box has a plastic stop that prevents the door from falling all the way open. Pull in on each side of the glove box where the stops are and this allows the glove box to fall open further. The glove box itself can then be removed from the three plastic pivot points. The glove box snaps onto the pivot points so all you have to do is gently lift up and away from the pivot points and the box will snap off. Be gentle so that you don't break either the pivot points on the glove box or the pivot points in the plastic bezel that is removed next.
2. Remove the plastic bezel that fits around the glove box. There are three 7mm bolts that hold this bezel in place. Remove them and gently pull the top portion of the bezel away from the dash. On each side of the bezel at the lower portion, there is a retaining clip. Gently pull on each side of the bezel and it will snap free from the dash frame. Remove the wire connector for the glove box light and the bezel can be removed and placed out of the way.
3. You will now be able to see the mode door actuator on the left hand side of the glove box area. You will also see that there is an aluminum box that surrounds the glove box door when closed. This aluminum box has a cutout in the left hand side that will allow you to get your fingers on the actuator. There is also room on the left hand side of the box to get a 1/4" ratchet and socket in there to remove the actuator.
4. There is a yellow wiring connector that is in the way and held in place by one of those ribbed plastic retainers. The retainer is pushed into the side of the aluminum box so remove the retainer and then disconnect the wiring connector. There is an orange safety retainer for the connector that should be pulled out and once this is done, the connector comes apart by pressing down the connector snap retainer. This will be self evident when you get to this part.
5. With the wiring pushed out of the way, you can now use a 1/4" ratchet and 5.5mm short socket to remove the two bolts holding the actuator in place. It is a little tedious and if you have big hands and fingers, it will test you a bit but the two bolts holding the actuator in place have the coarse wide threads so they come out pretty quick.
6. Once the bolts are out, you can remove the actuator and pull it downward to get to the wiring connector off the actuator.
7. The installation is as simple as reversing the steps.

After I installed the new actuator, the system automatically recalibrated itself. I watched it run the actuator back and forth. However, if you want to let it calibrate again, you can remove the 10 amp fuse that is located in the passenger footwell fuse box. The owners manual will show you where the fuse is located.

I hope these instructions help others out there with a mode door actuator issue. I couldn't find any instructions for a C6 during my research so I decided to post these.

 

Nice instructions. I had always been under the impression that the dash had to be removed to do this. As I was reading, I was thinking "who cares about the price of the actuator? The labor will be $1,000". Nice job...thread saved.

 

On more time!

 

It occurs to me that this thread is worthless without pics!
This is what confronts you when you get the trim bezel out.



You can get this view from just removing the glove-box door. Doesn't show much.



One screw is easy, it's right there! The other one is back behind the transmission housing and has to be done by braille.

 

AC Door Flap Actuator.
Great thread.
I too understood the dash had to be removed for this repair to the AC air diversion doors.
Yes, sure were correct; pictures make this thread a top 10.
Awaiting other co-member comments.
Great thread...Thank you.

 

So if im getting hot air from the drivers side and cold from the passenger side vents would this be the correct way to fix it ? I know it could be the dual zone controller also. I had the freon replaced at the dealership and so that shouldn't be the issue. All my research leads me to believe its the blender door. Does this fix that ? I seem to see different names for parts that are potentially the same. Thx

 

Great thread. Thanks for posting with the pics. Saved for future referrence

 

This is my present problem as well. Is this fix for a dual control system?
My drivers side blows warm air and my passenger side blows colder air.

 

Just a side note, the yellow connector that is mentioned in the steps to disconnect is for the passenger air bag. I would suggest disconnecting the battery first and let the systems discharge for about 20 minutes before pulling the seats (since they have airbags also) or disconnecting this connector.

Gary

 

Likewise, is this the fix?
Thank you

 

Same issue for me as well

 

Was this ever answered?

 

So ultimately my Freon was low, and as it started leaking down it first seemed to manifest as blowing cold only on one side before finally just blowing warm throughout. Once I had the Freon topped off it was cold on both sides again.

 

Just had my freon checked, so I guess I'll try the motor anyways

 

Update - changed out my blend door actuator (different model # than I thought, AutoZone has a dorman replacement).

Definitely tedious, and no extremely straight forward with which bolts but the write up that's been posted multiple time definitely gets you 90% the way there

Started the car back up, reindexed the AC doors, reindexed the windows and it's perfect!!

Thank you for whoever made this thread and suggested such a simple fix, $51 and I have AC again

 

The title of the this thread indicates that this is the replacement method for the mode door actuator (tells the HVAC system which vents to push air out of, floor/dash/windshield) but I have a suspicion that this might really for the blend door actuator, which controls whether air is being recirculated or coming in fresh. It does look like there is two screws and a mounting nub for the three mount holes on the part.

Based on part numbers, which ones have been done? I believe the AC Delco Part Number is 1574123.



This is the mode actuator - this is the one that this is a guide for, right? I hope so!

 

That's the part I installed - and it was done without taking the dash apart! Fixed my problems as well

 

Well, replacement AC Delco actuator installed, no change. Still get some clicks but air still only comes out the defrost no matter the setting on the hvac screen. Sadly this appears to run deeper.

Thoughts on next steps? The dealership procedure sounded pretty invasive.

Also, the plastic housing one reaches through for this fix was cracked and the diverter actuator looked new so it’s likely someone else already tried this method and they got the same result.

Bummer. That back screw was no fun indeed.

 

You almost certainly have HVAC codes set. The codes will not set a Check Engine light. The codes will not be visible with a generic reader. You can attach a Tech 2 or other code reader fluent in General Motors Y-body to retrieve HVAC codes and perform tests.

The piano roll is possibly shredded. GM calls it a "mode valve." You should be just able to see it through the defrost vent. It may be easier to see outside the car through the windshield.

If you can remove the new actuator and spin the shaft by hand, you should see the mode valve plastic sheet moving.

If the sheet is stuck and/or loose/torn, that's bad. If it's orange in color, that means it's the old design that was more failure-prone.

 

After changing this actuator three times out in a day (hoping a local replacement would magically work… it didn’t) I am hoping to contribute back to this thread.

I didn’t have a 5.5 mm socket, a 7/32 sae socket worked great.

I found getting the first bolt out with a ratchet was “easy” and can be done by contorting yourself into the passenger footwell.

The second bolt is behind and pita. I found this little **** worked really well with just enough torque multiplication for removal and installation. The big key was getting in the drivers seat and leaning over so I could use my dominant right hand.



It looks like the dealership I got it from replace this and tried to use a socket on the back bolt. The result is that the plastic around this access port is broken on my car now. Don’t do that!

On the last swap back to the AC Delco unit it took maybe 20 minutes after we waited (again) for the battery disconnect to fully take effect given proximity to the airbag.