i had this problem , i took of top casing , 3 screws at back then slide white top backwards , follow the silver tube from back to front
, at the front youll find some wire sensers these are limit cutouts , 1 looks like a small ceramic pin try pressing it in to reset it , put power off first , if it clicks in thats it , of course there must b a reason for it tripping but i reset mine and its still going
the fitter, October 2005