What was found
DURING DESCENT, FLIGHT ATTENDANTS REPORTED SMOKE IN THE CABIN FROM UNKNOWN SOURCE. PERFORMED SMOKE REMOVAL PROCEDURE & SMOKE DISSIPATED. ISOLATED BOTH RECIRC FANS, OPERATED INDEPENDENTLY IAW AMM 21-22-10, CHECKED OK. ADDED CARGO FAN & GALLEY HEAT, SYS CHECKED NORMAL. ACCOMPLISHED SAME WITH ENGS, CHECKED NORMAL. CHECKED BALLAST ON FLUORESCENT LIGHTING, NO DEFECTS NOTED. ACFT OK FOR SERVICE.