Ac won't work on a 07 dodge nitro

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clutch problem in the ac compressor pulley have it checked

I would say that with 2 lbs of Freon in the system that the high pressure switch is stopping the compressor from working and being destroyed from liquid on top of the pistons. An ac system works by compressing gas to liquid and then releasing that liquid through a small orifice into a vacuum created by the ac compressor .With excessive liquid then that turning to gas situation will not occur and liquid will get to the pistons and stop the piston movement. I recommend that you take it to a ac specialist and have the system pumped down into a receiver tank and then the correct amount of refrigerant gas added .

There are several switches involved in an ac system . There is a high pressure switch that turns off the compressor if the head pressure is too high (blocked system-excessive gas qty) and a low pressure switch that switches off the compressor when there is insufficient gas -(leaking system)/ Next some systems do not work unless the blower and the ac switch are both on ( prevents ice forming on the evaporator coils from lack of air flow ). That is the electrical side of things . Next there is a TX valve that allows the liquid refrigerant to become gas in the evaporator ( producing the cold air) that can become blocked . There is a thermostat that is attached to the evaporator fins that will shut off the ac compressor when the cabin temperature has been reached. Next there is an air/dryer accumulator that can become blocked from moisture and dirty oil that will affect the operation. Well that is all the points that can cause problems.
How does it work . The system is full of refrigerant gas that boils off at a very low ambient temperature . The compressor compresses this gas and turns it into a liquid refrigerant in the condenser (In front of the radiator ) This liquid is pumped to the TX valve which releases the liquid into the evaporator coil and as this area is in vacuum from the compressor sucking the gas ,the liquid going from a liquid into a vacuum boils off from the heat in the car . This cools the air in the car . The gas is then sucked back to the compressor where it is again converted back to a liquid . As you can see ,any items that are not working properly will cause problems because the circulation of the gas has to follow a set procedure or the compressor will shut down. Best advice is -if you having ac problems then take it to an accredited ac specialist and have the system tested for gas and leaks.

If the cooling system is full of liquid, the thermostat may not be closing when the engine is cold.

Check for a clogged line. Judging that the car is relatively new I don't think it would really be that. It probably just needs a recharge. Head to your local auto parts store and grab some an AC recharge kit. Doesn't take long at all and is relatively cheap.

The AC compressor may need recharged, or repaired / replaced. A lot of times what happens is through the winter AC units aren't ran so the seals recieve no oil and dry out letting coolant escape. Sometimes you can get lucky and a recharge (which contains oil essential for your seals) will do it - if they are too dry however, you will need a new compressor. You can have your AC unit recharged at nearly any dealership except in the state of California. Hope this helps.

The most logical reason for this is some sort of leak in the ac lines, causing low pressure-the low pressure switch then keeps the compressor clutch from engaging, to protect the compressor. The system needs to be inspected for any obvious leaks first (check hoses, fittings at the compressor or condenser, evaporator which can be hard to check due to it's hidden location)-a good way to find a leak is to charge the system with 134a that has dye in it, then expose with a blacklight.

sounds like your pressures were to high replace your compressor 2 to 350.00$ new dryer 80.00$ high pressure switch 40.00$ flush all lines and coils vacume and recharge self 500.00$. A shop 9 to 11 hundred probubly have your system checked yearly because AC pressuers fluctuate from season to season and if you dont need your AC in the winter Pull that fuse cause in defrost mode your AC is on.

you should be adding the 134a to the system the low pressure switch is doing its job by not allowing the compressor to kick on, it wont kick on until there is enough 134a in the system to be above the preset pressure for the low pressure switch.