What was found
CREW REPORTED, WINDOW LIGHTS OVER SEAT 5BC SEEMED TO BE GETTING HOT AND EMITTING A HOT PLASTIC SMELL. MAINTENANCE ISOLATED PROBLEM TO READING LIGHT AT 3A, LIGHT WAS DEFERRED. SMELL REOCCURED ON FLIGHT 5086 ON 4-7-98, MAINTENANCE FOUND OVERHEAD AND WINDOW LIGHT BALLASTS FOR SEATS 3,4 AND 5A TO BE CAUSING THE SMELL. REPLACED BOTH BALLASTS.