As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DOUBLE AC GENERATOR FAILURE IN CRUISE FLIGHT. MAINTENANCE TRACED THE PROBLEM TO SHORTED PINS E AND F ON THE LEFT AC CONTACTOR BOX - 2421-P15/J15. SUBMITTER STATES, THIS EFFECTIVELY SHORTS GCU NR 1/2 PIN D ON EACH (PHASE C) RESULTING IN BOTH GENERATORS TAKEN OFF-LINE.