As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LHR - FLT 104 - EN ROUTE JFK/LHR - DURING CRUISE, EMERGENCY LIGHTS ILLUMINATED AND REMAINED ILLUMINATED UNTIL LIGHT TEST SWITCH WAS ROTATED. AIRCRAFT PROCEEDED TO LHR AND LANDED WITHOUT INCIDENT. CLEANED CONTACTORS ON EMERGENCY LIGHT TEST SWITCH AT 1L DOOR. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)