As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT 0900, DURING CLIMB OUT FROM GMU TO 60J THE ALT, NR 1 AND NR 2 FAIL LIGHT CAME ON. RETURNED TO GMU WITH OUT INCIDENT. HAD ONE PASSENGER ONBOARD. GROUND RAN AIRCRAFT COULD NOT DUPLICATED PROBLEM. PERFORM A AROUND THE PATTERN FLIGHT AND PROBLEM CAME BACK. AFTER FURTHER TROUBLESHOOTING FOUND THE LOGIC MODULE INSIDE THE MCU TO HAVE A BROKEN CONNECTION PIN. REMOVED AND REPLACED MCU.