UK Car Repair: Radiator fan constantly on, vauxhall astra, radiator fan

Question
Hi
I purchased an N reg vauxhall astra which had an engine conversion froma 1.4 to a 1.6 out of an A/C Rreg astra.
Now all the A/C stuff is all gone/unplugged and the rad fan wont turn off , i've replaced the fan switch for a new one and nothing , still stays on .
On my old 1.6 it had 2 wires to the fan switch and this one has 3 wires , would be a case of swapping wires ?
Or is there a fuse for the aircon that i can take out to solve the problem ?

I have tried the 2 wire fan switch and the fan doesnt come on even upto temp

Please help
Thanks

Answer
Some fan switches have two settings or operate 2 different circuits.  Check that there is a feed to the fan switch then you can touch it to each of the other wires and see what happens. Regardless, the fan should go off with the switch disconnected so someone has fed it directly to make it run constantly, (not a bad idea in summer.You'll have to trace the wires back from the fan to see what has been done, you can then rewire it through the switch, OR, fit your own manual switch.