As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE FROM HIK TO SUU, THE LEFT AFT LAVATORY EMITTED AN ELECTRICAL BURNING ODOR WHEN THE LAV WAS FLUSHED. THE LAVATORY COMPARTMENT WAS CLOSED OFF FOR THE REMAINDER OF THE FLIGHT. MAINTENANCE OPERATED THE PUMP NUMEROUS TIMES, WITH NO DEFECTS NOTED. MAINTENANCE REMOVED THE PUMP AND VISUALLY INSPECTED, WITH NO DISCREPANCIES NOTED. MAINTENANCE REPLACEDTHE PUMP AS A PRECAUTIONARY MEASURE.