What was found
AT FL410, MACH .78, NOSE PITCHED DOWN -3 TO -5º, AUTOPILOT WAS "ON", FLAPS OVERSPEED LIGHT ILLUMINATED. FLAPS INDICATED 7º THEN 20º, VISUALLY FLAPS APPEARED TO BE BETWEEN 0 - 7º. - FOUND BITS 1, 2, 7, 8 SET ON CONTROLLER, SUSPECT A BAD FLAP CONTROLLER DUE TO FAULT CODES. REPLACED CONTROLLER CHECKED MECHANICAL AND ELECTRICAL PER CESSNA 650 MM CHAPTER 27-54-00.