What was found
SLAT DISAGREEMENT LIGHT ILLUMINATED WITH NO SLAT EXTEND BLUE LIGHT ON APPROACH. RECYCLED SLATS TWICE WITH SAME RESULTS. AIRCRAFT LANDED WITHOUT INCIDENT WITH NO SLATS AND FLAPS AT 40 DEGREES. MAINTENANCE INSPECTED T-DUCTS, ACTUATOR AND BELL CRANK MECHANISM. ALSO, PERFORMED SLAT ACTUATION SYSTEM TEST, ALL CHECKED NORMAL. DISCREPANCY COULD NOT BE DUPLICATED.