Originally Posted by mmarshall

OK, no problem. I didn't notice that, but I'm not in competition with anybody here....no trying to be. We're all here to help and advise each other. In fact, that's why, years ago, the automakers started modifying the A/C systems to allow heat to be added to the cold air blowing out. When they first started linking the compressor-use to the defog/defrost mode, without the ability to add heat, people were ****ing-up the window glass with outside moisture-condensation. I remember that was a problem in my late Mom's old 1977 Plymouth Volare.....though the very definition of the Volare/Aspen was problems LOL.

What I'd like to see is the ability to vary not only the amount and intensity of air-flow through the vents, but also to be able, in warm humid summer weather, to direct warmed/A/C air through the defrost vents for defogging, and, at the same time, have cool air coming out at face-level, in the dash-vents, for driver/passenger comfort. . I don't know if you have that on your LS460 or not, but no car I've owned yet (including the Lacrosse) allows that. It's all the same temperature, no matter which vents you use.

Originally Posted by mmarshall

I strongly recommend this for effective windshield defogging. If the A/C compressor is operated in the defog cycle without some added heat, the cold air from the compressor will chill down the windshield and cause moisture-condensation on the outside, which the wipers will then have to cle.

Originally Posted by mmarshall

There are six entire pages of heat / A/C / vent /defrost / defog instructions, including several pages on just how all of the automatic systems work in each mode and how to customize/program the modes and turn automatic systems on or off as desired. IMO, it's ridiculous. I just said screw it, went into the custom-settings, turned off all the auto on/off systems, and, when I need something, simply turn it on and off and adjust it manually. I find it works better, is simpler, more dependable, and, for my purposes, safer, because I know exactly what is going on in the system any given moment. The only auto-setting I still use is the SYNC function which equalizes the temperature coming out of the left/right vents. That, BTW, was where I also noticed the recent failure of the temperature-control regulator, which of course, needed that significant repair...that is apparently a common problem in some GM products, though the one in my Verano was OK, perhaps because it was more of an Opel product than GM.

Originally Posted by mmarshall

Yes, a number of vehicles are like that. That's to try and keep some functions from icing up, though I'm not enough of an engineer to know all the details. At very cold temps, though, one often does not need the A/C for defogging, as the air can't hold much moisture to start with at low temperature / dew-points , and simply warm air from the vents, without the A/C, sometimes does the trick.

Originally Posted by mmarshall

What I'd like to see is the ability to vary not only the amount and intensity of air-flow through the vents, but also to be able, in warm humid summer weather, to direct warmed/A/C air through the defrost vents for defogging, and, at the same time, have cool air coming out at face-level, in the dash-vents, for driver/passenger comfort. . I don't know if you have that on your LS460 or not, but no car I've owned yet (including the Lacrosse) allows that. It's all the same temperature, no matter which vents you use.

Originally Posted by mmarshall

Correct. It's an icon/symbol. Tap it for MAX / ECO / OFF. ECO, of course, runs it at a more-efficient setting.

Notice, also, one nice thing about the Lacrosse (and most Buicks). Buick integrates the screen into the dash, so there is no goofy-looking, tacked-on pod sticking up out of the dash like in many vehicles.