During the past 2 days at night it have been a little cool at night. What I have noticed I set the Climate control to 77 degrees to warm up a little. The car was warmed up and I felt cool air. I raised it to 80 and still cool air!!! Does anyone know what the reason is? Probally will take it to the dealer next week to get checked out. I just want to know if anyone has a idea on what this problem is Thanks for any input and advice.

 

I have an 05 TL and have the same issue. My first gen TL would control the blower and temperature to keep the cabin temperature at the desired setting, heater, AC, both air temp and blower speed.

On my new TL, the AC works this way, but the heater doesn't. No matter how hight I set the temperature, the air coming out is cool, and the speed of the blower moter is consistent - unless I crank it all the way up to the "high" setting (don't recall the temp, but it's above 80 degrees). Then the blower goes to high and the air coming out is warm.

This isn't my idea of climate control, you have to adjust it manually both to start and stop the cabin heater, and there's no in between, it's all or nothing. I just picked up my car ffrom the dealer after the TL's first service and they indicated on the service order that they were unable to reproduce. Of course I tried it, and it never works at I would expect.

Other 3Gen owners, does this seem right, or should the air temp coming out of the vent and blower motor speed vary depending on the variance between cabin temperature and the setting selected?

 

I agree with you guys. The AUTO setting on the HVAC is set to use the A/C at all times to condition the air so that it feels nice and dry. The down side is that the air is always cool. I've had to turn up the temps to 74 and high during the colder nights with the system set to AUTO. The car does seem to have a harder time maintaining warm air as it gets colder. The only way to remedy it is to turn off the A/C which will sometimes fog up the windows.

dsc888

 

I think the lack of heat problem is tied to the OTA flat-line problem.

I periodically have this problem, in fact I have it right now, and it either goes away or the OTA flat-lines, I toggle fuse #7, and everything works again for a few weeks/months.
This seems to be one of the symptoms before I get the flatline although I haven't really been tracking this.

I have to leave the TL at the airport next week so as a preventative measure, I think I'll toggle fuse #7 and hope I can start my car when I return.