As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED MAU 3 FAIL MESSAGE IN FLIGHT AND CIRCUIT BREAKER POPPED ELECTRICAL BURNING SMELL WAS PRESENT. CREW DECLARED EMERGENCY LANDED IN GREENSBORO WITH OUT INCIDENT AND TAXIED TO THE GATE. MAINTENANCE WAS DISPATCHED AND FOUND MAU POWER SUPPLY 2 TO HAVE A BURNT SMELL.