That problem would be something with the temp blend door, or the controller. Does it do the same thing on auto climate and on manual? To go from very cold to very hot, the blend doors are moving all the way around, so the problem isn't that they stick, but maybe the internal position sensor is bad on the motor, so it just keeps going since the controller doesn't know where the motor is (so it doesn't know when to stop the motor).Wow @Pretaco, you deserve a medal - both for your attempt and the documentation.
I paid the $1600 to the dealer a few years back to get it fixed - and while that problem hasn't returned, just this winter, a new one has...
When I set the climate control to LO it's freezing cold. When I set it up one notch (65) it's warm, and 66 or higher it's HOT.
I talked to the dealer, and they said that it'd be at least $900 for just the part, and about as much in labor to get the dash ripped out and fixed. At 11 years old, I think I'm gonna live with it. Of course, if you think this is fixable via the approach you used, I may have to start to tinker.
I am having the same problem, I was hoping to find a simple fix or answer too how I can fix it for summer is here and rolling the windows down won't cut it.... best truck ive ever owned minor problem, need some insight plzI've known something wasn't right with my Tundra's HVAC for the past few weeks and just never thought to dig into it because I've been so busy. I decided to Google my problem while stuck in traffic today and look what I found...
Heater stuck on defrost - TundraTalk.net - Toyota Tundra Discussion Forum
Unfortunately, they make no mention of a fix. The problem I am having is this. I can change fan speed, temperature in both zones, etc. but I get no air out of the vents on the instrument panel. The mode select swaps the zones on the screen, but does not change where the air flows from. The only vents working in front are the two on the top of the dash for defrosting the windows and the big one in the middle to defrost the windshield.
It is going to get really hot, really soon down here and I am praying that the "brain" of this HVAC control hasn't died on me. I have pulled the Nav head unit out several times, but I pulled the whole thing apart this evening and unplugged and re-plugged all connections to the HVAC controls and it still will not function properly. No wires were pulled loose either.
Anyone else experience this? What was the solution? Thanks!
You need to take the servo plate off to find the problem. I had a broken plastic lever shaft I had to epoxy back together. I will post a DYI hack in the next.I am having the same problem, I was hoping to find a simple fix or answer too how I can fix it for summer is here and rolling the windows down won't cut it.... best truck ive ever owned minor problem, need some insight plz
I have the exact same symptoms. Were you ever able to fix this issue? This thread is extremely informative.Had the same thing happen to me as of about a week ago. The vents are currently stuck on defrost (output from top of dash). I've felt that there was something wrong for the past couple of years or so as I had been hearing noises coming from the dash like something was loose in there. Hard to describe the noise but it sounded kind of similar to a very slight rattle or as if there was something that was not quite in place, like something was loose. As of the last month or two, I started getting noises inside the dash that sounded like motor(s) moving or attempting to move whenever I turned off the truck that would go on for at least 10 or 15 seconds. Now, it's just stuck in defrost mode, which is fortunate that way I can at least ensure I can drive without a fogged up windshield. Will have to research this some more but the above comments don't look promising. Truck is a 2008 base model.