As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AHS 1 & 2 FAILURE. HAPPENED IN CRUISE, AHS 1 & 2 ANNUNCIATORS. CAME BACK TO LIFE AFTER WE WERE ALREADY HEADING BACK TO BASE. WHILE TROUBLESHOOTING THIS ISSUE #2 SYMBOL GENERATOR FAILED PN 066-04021-1111 OFF SN 4932, ON SN 2635. BOMBARDIER TECHNICAL SUPPORT RECOMMENDED REPLACING THE EFS SWITCHING UNIT PN 071-00074-0500 OFF SN 1480, ON SN 1291.