Fabia diagnostic funny one..!

sorry if this is not the right place for this post, but i,ve tried it in the fabia owners forum and haven't had any luck so far...

i have a 2007 1.2htp classic (54bhp) (Fabia l model) . my epc light has been on for a while so i finally got it plugged in and it has shown up as brake switch problem. i've since put in 2 genuine switches and the epc light keeps showing up after the fault has been cleared abd car driven for 2-3 miles.

part number for switch is 6q0945511 and bought from skoda dealer. part put in by independent garage who are excellent and i've been uising them for 15 years with no problems so i'm sure switches have been put in right.

anyone got any ideas as I'm up for MOT in a couple of weeks and need the bugger out...!!!!

thanks dan