As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED THAT THE AUTOPILOT AND AUTOTHROTTLES DISENGAGED AND CREW RECEIVED AN AVNX MAU1A FAIL MESSAGE. CREW RAN QRH AND DECLARED AN EMERGENCY. WITH PASSENGERS BRACING, CREW LANDED WITHOUT INCIDENT. AFTER BEING CHECKED OUT BY EMERGENCY VEHICLES, CREW ALLOWED BRAKES TO COOL AND TAXIED TO GATE WHERE PASSENGERS DEPLANNED. MAINTENANCE TROUBLESHOT, R & R PSEM 2 AND FCM 3 IAW AMM AND OPS CHECKED GOOD. ACFT IS GOOD FOR SERVICE.