As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT DEPARTED. EN ROUTE EXPERIENCED RT ENGINE ALTERNATOR OVERHEAT MESSAGE ON EICAS. PIC TOOK CORRECTIVE ACTION AND RETURNED. TROUBLESHOOTING REVEALED RT ALT OVERHEAT SWITCH FAILED IN TRIPPED CONDITION. REMOVED AND REPLACED WITH NEW SWITCH. OPS CHECK AOK.