As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LHR - INFLIGHT CDG-JFK. CREW REPORTED RIGHT AC BUSS OFF LIGHT WITH CORRESPONDING ELECTRICAL BUS FAILURE. EMERGENCY DECLARED FLIGHT DIVERTED LHR LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED CURRENT TRANSFORMER T113. SYSTEM GROUND CHECK NORMAL OPERATION.