Ai rconditione wont blow cold air - 2000 Pontiac Montana

Check for blown fuse, you may have separate blower motor for rear. You may have master switch to turn off and on for rear A/C.
If so, the air wont be blowing at all.

needs to replace the heater core

check the condensor fan make sure its working and also see if anything might be restricting ais flow through the condensor

I have the similar problem with both my Jaguars, one is a 1988 Jaguar XJS, the other is a 1987 Jaguar XJ6, both blow COLD air out some vents while it blows warm air for heat. I heard it had something to do with the cold air blowing as a dehumidifier, I don't know if this is true, but it is really annoying to have both cold and warm air blowing when I need heat in these cold Canadian winters. If you find out please drop this website a note and let us know how you solved it. thanks.

check thermostat and coolant level

check cooling fan operation while ac on.If fan is working proper,will probably have stuck exspantion valve.

hello,seem you need to send your car to authorized dealer to scan the problem,maybe the solution is only synchronizing all the flap,ty

if it will not blow on high than, it is probably a bad blower resister! if air is not cold recharge system,

It is safest for your vehicle's A/C system to have a technician add/adjust any components. A/C systems are extremely susceptible to dirt and contamination. If you want to add freon, you can buy it at any parts store, and if you look under the hood, you will see two lines (silver w/ black hoses attached) They will have what looks to be a capped valve with a colored cap (usually black and green) You cant mix it up and put it in the wrong side (the valves are different sizes preventing this) make sure to use a gauge and add freon per directions on the can. Good luck

The refrigerant level may still be to low or the compressor is not working properly.