the compressor is driven by the belt on the front of the engine.

it will have 2 rubber and aluminium pipes going to it, one fatter than the other.

there will be either a single or twin core cable running to the electromagnetic clutch at the front of it - there will be a connector mounted on the compressor probably.

it can be done relatively easily and cheaply if you know the right companies to go to.

find the problem first, and we'll go from there.