Thanks.
I swapped switches and the seat worked. I cleaned all the pins of the passenger switch and they were shining like gold, put it back on and it wouldn't work! Took the switch apart and everything was as clean as a whistle with all the contacts having a clean action, all I could do was clean all the contact points. I tried to check the switches with a multimeter but the switch seems to be multiplexed....gawd knows what's supposed to be connected to what pin, it's like a 3D maze in there!
Anyway, I've adjusted the seat to where I wanted it with the driver's side switch in place and then I've disconnected the power plug on the passenger seat until I get hold of another switch.
Thanks for your help,
Mike.