Came across this forum while doing a search on air mix actuators. While not a Bonneville owner, I'm impressed with discussion. I own a 2001 Cadillac Deville. My problem is I'm getting heat & a/c ok, but the air flow is only coming out of the defrost vents. When I start the car there is a tick, tick, tick sound coming from inside the dash somewhere, that eventually stops. There is no blinking on the ECC, it seems fine. It'* just the air flow distribution is stuck. Is this the air mix actuator or something else?
Been looking for answers to this for a long time.
Any help is greatly appreciated!

Moved to it'* own thread.

This might help, not sure if your car is different. I'll go threw my service manuals and see what I can find.


It sounds like the actuator arm is either off, or stripped out, the clicking is more then likely the motor slipping. You will need to climb under the dash and watch the arms for movement.

I was able to find this. The air distribution actuator moves from defrost, default position, and then counts up. So I'm guessing the arm is stripped out and teh motro is just spinning inside the arm.

Mode Position
Value

Defrost
0 Counts

Mix-Blend
65 Counts

Floor
110 Counts

Bi-Level
220 Counts

Vent
255 Counts

So i need to replace the air distribution actuator?

Possibly. You might be able to remove it and then use some JB weld, that might work, it might not. If you want a new part, check out RockAuto Auto Parts They simply have some of the best prices you will ever find, they ship fast, and are very helpful.

thanks. i checked rockauto, no luck. i'll keep looking.

Try here, GM Parts - GM Auto Parts - GM Parts House USA I bit higher price, but has a lot of parts.

Finally located a good thread at CadillacOwners.com a forum much like this one. Apparently knowing terminology is key. They call it a "mode door actuator" or "blend door actuator". The part is inexpensive, but labor is unbelievable. The dealer wants $600 because they have to remove the dash. According to the forum, it can be done without removing the dash, but it is difficult and time consuming. One guy in the forum describes in great detail what he went thru. At one point taking a saber saw to remove a section of duct in order to gain better access.
Sounds like this part failure is pretty common, though the fix is not easy.
At any rate, thanks for your help.