hi
simple test ...(have actually just mention this on a previous reply 2 mins ago lol de ja vu )
anyway pop the bonnet ,start the engine ,,temp switch to cold ,fan to speed 4 aircon and recirculation switch on..now go to front of car and with in a couple on mins the rad cooling fan should run at half speed,which will prove that the aircon is working ...also 1 aircon pipe will be very hot and the other very cold ...if the fan doesn't kick in then as previously said the resistor pack will be duff...it's situated top right of fan cowl under coolant resovoir ...it's 1 plug ,and held in by a torx screw ,only costs £18,takes 2 mins to fit ,also i would get the system recharged ,as no manufacturer actually fills the system fully ,hence companies like kwik fit can state they won't charge you if they can't make your car colder.also you loose about 15% of gas a year...grandes take 500,learned that when i recently did an aircon course,used my grande as a gunea pig ...and suprisingly it was nearly empty ..it then passed the vacumn test etc and hasn't lost a bit in 4 month