Having some issues with the climate controls in my '05. This summer we drove down to Florida and noticed that while I was always hot, my wife was always cold no matter what settings we were using. One reason we took my car instead of her car was so we can have out own temp controls. Now that winter is here, the temp differences are even worse.

Symptoms:
- Passenger side is always colder than Driver side
- Vent controls all appear to work properly (floor, vent, defrost)
- Same behavior on heat and A/C
- Manual temp changes take 3-4 minutes to change and the swing is drastic

I have had it to the dealer twice now and they have not been able to pinpoint the issue. The first trip they charged the freon and they thought that would resolve it. The second trip they went after the cooling system thinking their was air in the system. No luck. It doesn't really help that each time I take it to the dealer, it won't act up much for them. Then without fail the next day driving to work, it will be messed up again. I spoke with the mechanic and based off of my description it sounds like one of the air-mix motors may be starting to fail. However he isn't sure which one and didn't want to replace the wrong one and me get charged for both. I am not under warranty at this point. The dealership has been great and hasn't charged me anything for the last two service visits.

An example of the temp swing issue. My normal commute home from work would usually have me set the temp to 72 on auto and start driving. Usually after about 10 minutes I would drop that down to 68. Now it is at 72, then after 10 minutes I drop it to 68. Still f'ing hot. So I drop it down to 62. It stays blowing hot air for a few more minutes, then the air swings to ice cold. Bump it back to 68 and it takes a minute or so before the air comes back to being warm. Now it takes me controlling the fan speed and opening windows to regulate the temperature inside my car which sucks.

 

There are temperature sensors on the lower part of the dash.

Make sure that they are connected and able to access ambient cabin air. If they fall out of their places, they measure air temperature behind the dash.

On post 5, page 20-82 on the scans, check out the right side of the page. (A) points to the in-car temperature sensor. Make sure that it is hooked up right.
https://acurazine.com/forums/3g-tl-2004-2008-93/those-who-have-service-manual-i-need-help-3g-garage-f-052-a-557238/

Mine started acting right when I put my sensor back in.

If this does not work, then good luck - I have no idea.

 

FYI, there is only one sensor. It's less than $30 shipped (online discounted price). It could be faulty and causing your problems, but you don't see much about them failing.

If you have a multi-meter, you can test your sensor.

 

Thanks for the info. Of course like usual with this car, each time it goes into the dealer for an issue, it magically goes away for a week or two. Since I got it back from the dealer, the HVAC is working perfectly. So still waiting for it to act up again so I can work on troubleshooting more.