Ford Sierra Saphire Window Problem

[Somerstown]

I have a Sierra Sapphire 1992. Niggling problem is that whilst for over a year the electric front windows have worked fine, today the passenger one would close but not reopen. Driver side works fine. I have checked the connections on the back of the switch and sprayed the switch and motor with WD40. But still no luck. Anything else I can check or try please? Don't want to buy a switch and the motor for the window is at fault or the other way around.
Thanks for any helpful suggestions.

 

[gregers]

check the rubber boots,between the pillars and the door.the wires are usually very tight and they have a tendency the fray and break,
either that or the switch could be fubared.
can you open and close said window from the drivers side ok?

 

[Somerstown]

Thanks for the ideas, I will check out the rubber boots,between the pillars and the door for frayed wires. (Friday I should have time).
There are just two switches for the front windows, one for each side. The connection positions are different, so cant swap them to try that.

 

[Somerstown]

I could not see a problem with the wiring near the door. But tried respraying the switches again with WD40 and it now works. Just hope it continues working!
Thank you for the ideas.