When foot brake pedal is depressed too hard i.e. emergency stop or for M.O.T the pedal clicks/snaps forward and makes the brake lights remain on,if left like that when you are driving they start to brake themselves. The foot pedal has to be pulled forward by foot or hand to click back into position, then it is ok again. Does anyone know why this would be, is there a worn part or is something broke on brake pedal linkage. Would be grateful of any ideas,as this has made car fail M.O.T.

Eventually got round to fitting a new switch as per your advice and it has sorted the problem. You need to be a bit of a contortionist though. Thanks!

Switch has worked for couple of weeks, but for some reason the brake pedal seems to be pushing the switch in when driving thus applying brakes. Have had to reset switch several times but keeps doing it, [i'm not pulling pedal forward]. should there be a bit of play in the pedal? could this be due to some other problem/malfunction?