What was found
(CAN) BURNING ODOR IN CABIN AROUND ROW 11 & 12 OVERHEAD BIN AREA. ODOR DISSIPATED WHEN CABIN LIGHTING WAS TURNED OFF. MAINTENANCE DISCOVERED BURNED PIDC SPLICES OVER PASSENGER SERVICE UNIT NR 4 (RT FWD). SEVERAL SPLICES WERE REPLACED ON BIN HARNESS USING SPLICE, SUPPLIMENTARY INFORMATION AND INSPECTION PROCEDURES: A SIMILAR SITUATION ON ANOTHER AIRCRAFT THE PREVIOUS MONTH REQUIRED RECTIFICATION OF SEVERAL SPLICES AND SOME WIRE CONNECTIONS. THIS PROMPTED A FLEET CAMPAIGN DIRECTIVE FOR ALL DH8 AIRCRAFT IN OUR FLEET.