What was found
3R, 2R, 2L SMOKE DETECTORS WENT OFF IN FLIGHT, NO SIGN OF SMOKE, LIGHT SMELL (FLIGHT ATTENDANTS DESCRIBED AS SLIGHT ELECTRICAL SMELL). RAN ALL GALLEY EQPT, TURNED ON ALL CABIN LIGHTS, RAN PACKS WITH ENG AIR DOORS CLOSED AND NO SMOKE OR ELECTRICAL SMELL IN ANY AREA. CLEANED CABIN TEMP SENSOR FILTERS, LAV VENT FILTER AND RAN ENGS TO HIGH POWER PER PFHB WITH PACKS ON. UNABLE TO DUPLICATE. REPLACED SMOKE DETECTOR.