HELLO, I AM NO EXPERT ON THIS, BUT CAN YOU HEAR MOTOR MAKING A NOISE, IF NOT IT MIGHT BE THE SWITCH PLAYING UP , IF CAN, SWAP ONE WITH THAT ONE, AND IF THE SAME AS MY CAR I HAVE SAME PROBLEM AT MO, AND I THINK MY CABLE HAS BROKEN, FROM THE ELECTRIC MOTOR. SO BEFORE YOU GET INVOLVED WITH THAT I WOULD TRY AND CHECK OUT ALL ELECTRIC FEEDS AND AS I SAY THE SWITCH OR A LOOSE WIRE. IF THAT ALL OK , THEN SUSPECT BROKEN WORKINGS
KEITH JOSLIN, October 2008