Help No Air Con

Hi can anyone help my 1996 p38 2.5 dse rangie air con isnt working heard people talking about the clutch ! On my other cars ive had when putting the air con on the car surges as the air con kicks in nothing happening to my rangie ! what shall i check now please help !!

have a look under the bonnet and see if the clutch is spinning when its on low! if its not tap it with a spanner and see if it then grabs? i had a problem with lack of voltage at the clutch and it wasnt enough to pull it over, i gave it a tap and it would fly across. with the engine off you can see the movement when you press it and this is done by electromagnet when power put to it.
you can check the voltage in the wires that disapeer under the pulley on the compressor to see what you have, i pushed the multi meter probes through the insulation of the wires to do this.....

the clutch hes refering to is on he front of the A/C pump. start yer injun with the A/C off and look at the front of the pump. it should be stationary. then get some one to switch on the A/C, there should be an audible click and a possibly a drop in injun RPM. but the important bit is the centre of the A/C pump pulley should now start to turn