if the switch doesnt work on 1 2 3 or 4 try a heater resistor which is under the glove box it cost me £15 second hand beforwe you go and buy 1 check with a tester to see if theres any power coming through on to the connectors if that doesnt do the trick its got to be the heater motor which also costs around £15 which is right next to it again use a tester to see if theres any power coming through
