The heat will not work. No heat.

Need a little more info but typically upscale cars will run the AC compressor even when not needed. This assists the car with humidity control in the cabin, the heater can easily heat the air that just got cooled and removed some of the moisture. Look for an economy setting, or a way to turn climate control off.

Possible bad blend door actuator .some gm cars can be relearned to the new climate control head

I would start with checking the blend door under the dash that controls temp.

Pull the heater control panel out of the dash and inspect the blower speed control switch, look for signs of a burnt connector to the switch, it will be discolored looking, if this is the case replace the switch and install a repair connector

Geraldine,I would venture that the resistor board,usually mounted near the blower motor,has almost gone all the way bad. Have someone check it. Of course,it could be the blower speed selector switch,but probably not.
don-ohio (:^)

i would like to ask you that , Did the problem come on suddenly or was some previous action or work done......

I have a 2000 pontiac grand prix with a digital climate control system. The heat quit working, it doesn't blow out any heat. Now that it is warm outside the air stopped blowing out any air. The digital temperature on the climate control is not correct. When it states that it is below 30 degrees on the ext and it is warm outside the air wont be cold. Once it starts going above 30 degrees the air gets colder. Today the blower stop working all together. Was told it maybe the climate control unit was bad. You can hear the door opening/shutting when you switch the temp from cold to hot. But there was no heat blowing out whatsoever in the winter time. Could you please give me your opinion on whether or not it is the climate control unit or something else?

I am sure this switch was tempered with and rewiring wrongly done. If the switch is okay, get an expert to do the wiring for u. If not, pliz replace. Good luck.

Your control switch is worn out - replace it (or have it replaced). The squealing sound you hear when you turn is probably the power steering belt (worn out or just loose). The power steering belt is driven by the water pump pully which also drives the alternator - check both of them. Retention or replace as needed.

Is # 5 the high setting ? if so then you blower motor resistor is bad