As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 1758 - IAD - FLIGHT CREW REPORTED ACFT STUCK IN ESSENTIAL POWER MODE ON CLIMB. CREW PERFORMED AIR RETURN AND LANDED UNEVENTFULLY. IAD MX REMOVED AND REPLACED RELAY K0097 AND PERFORMED OPERATIONAL CHECK SUCCESSFULLY. ACFT WAS APPROVED TO RETURN TO SERVICE.