What was found
FLYING AT 40,000 FT, NOTICED YELLOW X THROUGH BOTH PITCH & SPOILER INDICATORS. NO OTHER INDICATIONS OR CAS MSGS DISPLAYED. ACFT SEEMED FINE BUT SHORTLY THEREAFTER THE AUTOPILOT WOULD NOT FOLLOW COMMANDS. TURNING AUTOPILOT OFF IT BECAME APPARENT THERE WAS A FAILURE OF PITCH CONTROL CAPABILITIES. REMOVED FAULTY FCE 2 UNIT. INSTALLED MODIFIED FEC 2 UNIT & PERFORMED OPERATIONS CHECK & SPOILER RIGGING PROCEDURE. NO CAS MESSAGES PRESENT. PITCH CONTROL OPS CHECKED GOOD. FUEL INDICATION NORMAL. ALL MX PERFORMED IAW MM TASKS 27-03-01-400-801-A & 27-60-00-820-801-A.