AC: Center two vents don't blow air. Outside vents do work. What could be the problem?

2nd Gen Tacoma, 52,000 miles.
So it's summer and I just realized not all my AC vents work. The outside ones do blow cold air, but it's not that cold. The inner vents on the dash don't work at all. No air movement. What could be wrong?

Has anyone else experienced this?

Update:
This is embarrasing. After reading your helpful posts, this Sunday I finally resolved to look under my dash at this problem. But this post by TacoLV got me thinking. Oh, man you guys. TacoLV suggests I try messing with my vent selector, and that helped tremendously. I hadn't looked at the vent selector. Here's what was wrong. The vent was set on defrost. I now must escape from the public view and go back to the darnkess of anonymity and solitude. Never accept advice from me. I am dumb. Thank you so much for your help. My air conditioning always worked well, but I was too ignorant to know it. Thanks again, everyone.

 

Here is the AC Unit. I don't know how it couldn't blow out unless there is something in there like a dead rat?

Maybe check the Mode Control Servo flapper. Remove the servo motor and then move the flapper by hand to see if it will work properly.

 

Thanks for your help.
How fun! It's like playing Where's Waldo? But wait . . . is this under the dash or in the engine compartment?

 

Dash

 

Here’s an informational video on how to remove heater core (not saying this is what’s wrong here). Helped me visualize it better

https://youtu.be/UKr5LlzM15k

 

When you turn the dial does it move to feet, and then the windshield?

 

If you've seen the vent system under the dash, it's hard to imagine how the center vents are not getting any air. Very weird. The airbox door either directs air to all the dash vents or it doesn't. That's how it looks to me.

 

This.

 

It is behind the dash on the inside of the cab ( like behind and below the stereo ).

See the Mode Control Servo. It is under the dash on the passenger side and can be gotten to easy if you remove the glove box assembly. Remove the servo and test the lever that it operates by hand to see if it redirects air to the proper locations. I think the servo is defective, but that is only based on a hunch and knowing how it is supposed to work.

If you move it by hand and get the proper air flow I would replace the mode control servo motor. It is an easy job and cheap relatively.

 

That is a first class reply. Thank you so much! After I catch a moment to do this, I will report back to the forum.

 

I had a problem similar to this on a dual zone ac, vents on driver side were hot while all other vents were cold. Thought the blend motor was kaput, but had the system evac and recharged and it blew perfect again. Just a minute amount of refrigerant missing and the system can't blow cold air efficiently.

 

This case most definitely sounds like an actuator . As mentioned above , try messing with your vent selector and see if anything changes . You should be able to see it by peeking behind the center console area.

 

Has any repair work been done that involved the dash or things that live behind it?

Took my '06 Avalon in for a cracked dash recall a few yrs. back. When I got home, I noticed one center vent blew little or no air; the other seemed to blow about the same as it always had.

Went through the usual grief one goes through to get this resolved at a dealership, but it eventually got done.