1997 chev. suburban air question

[x1957x]

 My 97 suburban with a  5.7 motor has air issues. I want to recharge the compressor but the question is. How do I test it to see if the compressor works before filling with freon? I turn it on and I dont see the compressor under the hood kick on. If out of freon will it still kick on the clutch wheel? Also, what type of freon does this year and model use?

[Jeremy airjer W]

If the system is to low it will not close the low pressure switch which allows current to the compressor. The compressor can be jumped with a power and ground straight from the battery to see if it will turn on. The system is controlled through the VCM.

 

a 97 should be r134.