ABS and T/C warning lights

[grandpa_spec_F6]

I know I posted a thread here before about this however rather than threadmine I am starting a new one on the advice of another forum member.

Roughly 3 months ago the traction control lights and abs lights were coming and going as they pleased, however now they are permanently ON.

I saw a local mechanic who advised that his diagnostic tool could not even detect ABS being there, and concluded that the module was stuffed and i'd be up for around 600 - 700 dollars fitted, which being a uni student was like a fist to the face, although he rather enjoyed my reaction.... as did my girlfriend (so much for moral support eh?)

I read that you could clean the sensors and having no idea where to find them I took the rear wheels off and covered them in brake cleaner, took it for a test drive and gave the accelerator a boot (with the wheels on) and SUDDENLY warning lights disappear... YAY! says me, until I get 100 meters down the road and BAM, my dash is a Christmas tree once more :(

Trawled through the forums for any picture of what the blesed things were and finally phoned Mr Hardware, found the bloody things which are so neatly tucked away you cant get to them with ease, sprayed some cleaner onto them however after a test drive this yielded nadda...

A final touch was removing the rear seat and checking the plugs which could have been bumped installing the sound system wiring however these were fine.

So there you have it, anyone got an idea?