First check if compressor is rotating when AC switch turned on. If no, then either clutch failure or no power to clutch. You can follow the clutch wire up to the wiring harness beneath the crossmember covering the top of the radiator, stick pin in wire, check for voltage without major disassembly. If no voltage look for blown fuse. If voltage then clutch failure, must replace entire compressor. If compressor needs replacement, then look for root cause. Most likely the suction line has a point of constriction or collapse. If so, its often visible if you know what to look for or feel for. Regardless, do not reuse a collapsed line and do not replace it with new KIA or OEM. Its a design defect. There is only one replacement that eliminates the point of constriction. It is only sold on eBay:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=181880844799You can buy a new compressor and filter dryer together at Advance Auto Parts and get a Limited Lifetime Warranty on their "Tough One" brand. While they seem to honor their warranty, somewhat is disbelief of what is says, I have gotten a defective new compressor, so be aware that their quality may not be as good as their warranty. You can remove old compressor and install new yourself if you can find a means or mechanic to remove and capture the freon down to zero pressure and after reassembly a means to run a vacuum for an hour. Illegal federal offense to dispose of freon to atmosphere. PRESSURE MUST BE TOTALLY REMOVED TO ZERO BEFORE DISCONNECTING THE COMPRESOR HOSES. "O" ring gasket connections must be flushly seated with no visible gap, otherwise will blow out upon refilling and you will have to start the vacuum process over again. Most auto part stores and even BigLots ($6) sell freon in 12 oz cans with pressure measuring dispensor hose for refilling your system.
