i have a 95 cherokee and i think that the compressor is going. when i turn on my a/c and, or defroster. it starts to click and whine, and when i turn on my vents it doesn't make the noise so could it be my blower motor?? i have no clue what it is, my guess is a compressor

 

Is the noise in the cabin or under the hood?

 

under the hood

 

Sounds like your out of freon. Check the pressure in the line.

 

out of freon, the compressor wont come on at all. if it is cycling on and off then it may just need to be charged. if this is the case you have a leak somewhere and it should be located and fixed properly. the system needs to be evac-ed and recarged to the right amount for it to work the way it is supposed to.

 

it has pressure but wheni checked it , it was warm not cold from under the hood. and the compressor turns on just when it does it makes a clack clack noise but the air coming out of the vents is cold

 

Compressor clutch may be going bad then.