right then, update time,everything has been checked out and is working exactly as it should,on off switch,de ice switch,pressure switch,wiring to ecu all tested so it looks as though the ecu isnt earthing it out to switch it off or it is the chip which isnt compatible,the ecu numbers are exactly the same as yours dave minus any biro writing,i now need to find someone else with a p8 with aircon to check their numbers as well,is yours deffo from an aircon model dave? cheers for the help