fan switch/ac

[perthtx5]

Hi i am new to this site and have read quite a lot of problems that people have had with there telstars which will come in handy if they happen to me.
I currently have a problem with my 88 telstar tx5 ghia, when i switch fan on to position 1 or 2 the ac compressor kicks in but no fan speed, when I put it to 3 or 4 fan cuts in but ac compressor turns off. I pulled the unit out of dash thinking it may be worn connectors, there is six wires running into the fan speed box 1 for each speed ,earth & power i presume, there is power to possistion 3 & 4 but not 1 & 2. So i hope somebody might point me in the direction i should be looking as everything else seems to work like it should.
It also might be the fan motor itself but i cant find where the power for 1 & 2 comes from.
Cheers for any help!