AC Blowing Hot Air on everything but LO
 

The AC has been acting weird for the last two week. It seems to only blow hot air in all the settings except LO. The image attached shows it set to 65, recirculation on, and AC on. Still blows hot air, feels like 75-80. It started of being randoms, some times hot, some normal, but now it's pretty much only hot unless its at full LO.
First guess would be AC needs recharge, but the car isn't even at 15k miles yet.
Asking here before going to the dealer, because if it's an easy fix I'd rather avoid them. Thanks.

Sounds like a recharge to me but as you said it is really early in it's life for that. Did you do/have done any work lately that could have damaged a line?

You might check to see if the clutch on the compressor engages when the AC is turned ON.

If not, you might check the fuse.

If the clutch engages and the unit is blowing hot air and the fuse is good, I reckon it's time to have the system checked to make sure it's charged.



humfrz

Another possibility given all the electronic controls, taken from another vehicle and may have no relationship here to any form of reality but worth mentioning.

Our 2004 Suburban has electronic triple zone controls (Left Front/Right Front/Back).

It is possible for the various gates to get out of synch with the controls and have exactly what you describe happen (heat when you should have cold). There is the HVAC equivalent of the "pedal dance" you can do to get everything back in synch. I've had to do it twice in the last five years.

This is one of the reasons I'm perfectly happy with the old-school controls in the FRS.

I'm pretty sure it engages because it was working at times before and I can hear the change in engine idle. I'll check the fuse at this point, and if it's not that then I'll just take it to Toyota since it's still under warranty anyways, either they recharge it or fix whatever is broken.

Did you mean the Suburban needed a resynch or your FRS?

Good plan.

Please keep us posted on what you find out.


humfrz

Suburban, but thought it was at least something to check on the BRZ. My FRS has manual controls so that isn't a problem there.

Mine seems to do the same, but dependent on outside temps (reading thru the gauge cluster). I have to set my a/c to a temp close to or lower than what it is reading for outside ambient temp to get cool air through the vents. :iono:

Hey, did you find a solution?
I know it’s old post, but I have the same problem on my GT86 TRD from '19
The AC will blow hot Air on everything but LO, on LO it will blow really cold Air.

Stop with the A/C recharge and blend door nonsense. A bit of logic guys, if it's cold on low, and can change from cold to hot, A/C is fine and blend doors are fine.

The way an automatic AC system works is you give it a temperature target and it tries to bring the interior air temp to that target, except on low where it's target becomes "fuck everything go as cold as possible". If it's trying to hit a temperature target that means there's a temperature sensor in the system, and when temperature sensors fail, they typically fail to -48 degrees Celcius. If the automatic A/C is trying to warm you up no matter what temperature you ask of it, it may be because it thinks you're cold.

Easy diag. Read auto A/C DTCs and live data for interior temp. Continue troubleshooting accordingly.

Anyinefoud a solution to this having the same problem after having the evaporater changed

Did you find any solution to this ???

It feels like when ever I increase the temp just a bit the doors open completely

Take it to a professional who is willing to logically approach the issue. At least read up on the subject. Link in my sig line.
https://i.imgur.com/vua9239.png