What was found
ELECTRICAL ODOR IN CABIN. THE FWD LAV FLUORESCENT LIGHT WAS ARCING CAUSING ELECTRICAL ODOR. THE CB WAS PULLED AND THE LAV INOP'D FOR REMAINDER OF FLIGHT UNTIL MECHANIC COULD EXAMINE LIGHT ON GROUND. MECHANIC RESET CIRCUIT BREAKER AND DETERMINED LIGHT TO BE OK FOR SERVICE. IF FLOURESCENT LIGHT TUBES ARE NOT INSTALLED PROPERLY IN LIGHT SOCKETS, ARCING CAN OCCUR. BOEING 777 MT 33-002 GIVES INSTRUCTIONS TO ENSURE THAT FLOURESCENT LIGHT TUBES ARE INSTALLED FIRMLY INTO RECEPTACLES TO PREVENT ARCING.