If the a/c clutch does not engage, the compressor cannot push refrigerant thru to the condensor, etc. etc., etc.

Turn off the car. pop the hood, Stand in front of the engine bay area. From this point, look towards the right side(drivers side) for the radiator hose on top of the radiator(right side of radiator in this case). Below that is a serpentine belt - single belt that drives all of your principle accessories..ie..power steering pump, a/c compressor, alternator, etc.

Not far below the radiator hose just mentioned is a cylindrical shaped cannister. This is your power steering reservoir. There's a pulley in front of it and the serpentine belt drives that pulley.

Beneath this pulley(further down) is your a/c compressor. The serpentine belt turns downward to drive it.

The a/c clutch is 3.5-4 inches in dia.(outer part). round shape and it's at the front of the a/c compressor.

Start the car, leave a/c off. Shine a flash light down in the direction of the a/c compressor. You'll see the serpentine belt free-wheeling the a/c pulley- a/c is off and that round shaped piece(clutch) at the front of the compressor will not be moving.

Now turn on the a/c. The round shaped piece(clutch) at the front of the a/c compressor "should" engage the compressor and also turn with it. If it's not turnning, then you should have a qualified tech. examine the system.