As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
POWERED UP AIRCRAFT FOR PREFLIGHT. FMS SCREEN STAYS BLACK AND SMOKE WAS COMING OUT FROM UNDER FMS. FOUND FMS GNS-XL. CONTACTED EMPIRE. REMOVED AND REPLACED GNS-XL IAW CE560 MM 34-61-03. OPS CHECK IAW GNS-XL FLIGHT MANAGEMENT SYSTEM OPERATOR'S MANUAL.