As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT DIVERTED TO LHR DUE TO EN ROUTE LOSS OF RIGHT GENERATOR. FLIGHT WAS RELEASED WITH INOPERATIVE BACK-UP GENERATOR. FLIGHT PLANNED TO LAND OVERWEIGHT. LANDED NORMAL WITH 98,200 LBS FOB. THE RIGHT GENERATOR CONTROL UNIT (GCU) AND INTEGRATED DRIVE GENERATOR (IDG) WERE REPLACED. THE FINAL FIX WAS TO REPLACE THE IDG WIRE HARNESS.