Auto Max AC Mod

Easily located and replaced?

 

Easy is a relative term. Some have said its a bit difficult, I did not. Here is some more info:

https://www.toyotanation.com/forum/...880-08-c-air-door-actuator-servo-problem.html

https://www.tacomaworld.com/threads/recirculating-air-not-working.535435/

 

So is my issue with the air inlet servo motor, or the air mix control servo motor?

 

If this were mine I would look first at the air inlet servo. Its the one that controls recirculation.

You can also "listen" to the servos. There are three servo motors: the mode control, the temp control, and the air inlet/recirculation control servo. The first two are located on the right side of the HVAC box (right side as viewed sitting in the pass seat), and the last is on the inlet just below the grill but inside the cabin. This last one is on the left side of the air inlet as you would sit in the pass seat but you have to reach high up, above the cabin filter, and removing the glove box helps.

For a normally operating system, with the key turned on but the engine not started turning the mode control knob (air at face >> defrost >> and then back) you should hear that servo run and flaps inside the HVAC box move. Now try the temp control knob and rotate from cold >> hot, you should hear the servo motor run and may hear the flap door inside the HVAC box move. Finally, for the air inlet/recirc servo you should be able to push the red button, have it light, and hear its motor and flap.

I noticed from an earlier post that you may have modded the wiring some. Never hurts to check that one.

 

Thanks for the info & tips. Yes, I did the auto Max AC mod some time ago. The recirc has been working fine when the button was pushed, until just recently, when I noticed nothing changed when I pushed the recirc on button. I'm going to check the wiring this weekend. I thought about taking it in to the dealer, as I have an extended warranty, but 1) they might find the mod and say they won't work on it since it's been modified, and 2) I'd rather just fix it myself if I can find the problem.

 

Subd

 

Went into the area behind the glove box today to check out the recirc issue. First thing I noticed right away was the door on the cabin air filter compartment was not shut, probably left open by the last guy who replaced the CAF at the dealership (I know, I know). I could see that the filter looked exceptionally dirty, so I pulled it out. It was full of crap. Our neighbor has horses, and he refuses to clean up after them, just rake it around with a tractor. So when the wind blows, it all comes our way. So the filter was pretty clogged up with horse crap powder. Took that out, cleaned it up, blew it out with compressed air, and put it all back in. Guess what? I can now tell the difference when I turn on the recirc button. The combination of the clogged filter and the filter compartment door open seems to have affected the air flow, to where I could not tell that the recirc was working. It seems to be fine now.