Mines broke and the wire to the air con was split so easy fix.

Can u hear the pump kick in when u switch it on?? If not then the pump is gone or wire is cut.

If the pump is going but just no cold air, you'll prob need air con recharge kit.

Buy this, good stuff: -
http://www.halfords.com/webapp/wcs/store...tegoryId_165632

You can usually buy this stuff of ebay for half price!!