2008 GrandPrix no heat/no ac - has coolant and refrigerant what could be wrong?

You say you can hear it blowing but can you feel it blowing out of the vents ?

Air blows out of all vents and to the appropriate position on the temperature control switch.

Sounds like you have a bad temperature control switch. It's not controlling the door in the heater box that opens and closes switching from heat to A.C.

You miss understood me, the control switch control is working fine. If you switch to the defrost position it goes to the defrost and all other vents are switched off. The fan blows to the appropriate speed based on the fan speed position. I don't think it's the Temperature Controller. When it comes to the AC, the compressor is not coming on, when it comes to heat the hoses in the engine compartment are hot but it doesn't blow any hot air!!

I'm currently looking at a print out of all the fuses and relays that are associated to the HVAC system and there are a couple more that I missed. I got a PDF copy of a repair manual it's not the same year but it's close enough.

If you read my last answer you will see I said temperature control switch same as temperature controller that switch not only controls that door in the heater box but it also controls the the A.C clutch coming on because it senses when you lower the temp.

ok, even if it switches to defrost, to the vents, to your feet. I can hear the door making the switches and the air blowing out of the correct vent.

The main word I would like you to focus on is temperature not switch over switch that changes the air from defrost to vents they are to different switches.

Ha! Ok, so there are two items in one! Because it has a push button to manually turn on the AC or it will auto select based on temperature set on the controler. The AC light comes on if you lower the temperature below ambiant or if you manually press it either way the compressor doesn't come on.

I still say there is something wrong with that switch. To bad that it's a all

To bad that it's a all in one switch.

You may want check in a repair manual to see what it means when you lower your temp your A.C light comes on it may tell you exactly what's wrong or ask a mechanic at your GM dealer ship. Sometimes they are nice and will tell you what what your problem is. It may be something simple who knows with vehicles these days.

Well this might be just me trying to explain the non operation of the HVAC. But it's simple set the temperature to let's say 60 and the fan is set to auto, the light bellow comes on showing the AC is supposed to kick on (compressor) but it doesn't. No cold air blows out the vents the engine RPM doesn't adjust for the extra load by the compressor coming on (which it doesn't) so to me it seems that the temperature controller and the AC automatic seems to be doing what it's supposed to. But since the compressor nor the fans come on well it just never produces cold air.

Ok, I was thinking of finding the low pressure switch and jumping it to get the compressor to fire up and check the line pressure. But what gets me is the heat it should be simple hot water in the hose, luke warm coming out the hose so I just don't get it.

OK, that makes sense if it's too hot it shouldn't. OK, now on the clogged core is there an easy way to unclog it?

I have the same problem with my heat and a/c; what did you do to actually correct the problem?