As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMB-OUT OF EBLG, PERFORMANCE MANAGEMENT SYSTEM (PMS) LIGHT ILLUMINATED IN FLIGHT AND AUTOPILOTS "A" AND "B" WOULD NOT FOLLOW FLIGHT MANAGEMENT SYSTEM (FMS) COMMAND. AIR TURN BACK TO EBLG. NO FUEL DUMPED. OPERATIONALLY CHECKED IN ACCORDANCE WITH DELCO OPERATIONS MANUAL, P/N 7891920-415. COULD NOT DUPLICATE FAULT.