What was found
ON DEPARTURE, FLAPS FAILED TO RETRACT COMPLETELY & STOPPED AT 5 DEGREES WITH SLATS EXTENDED. ON ARRIVAL, MECH NOTED BITE CODE 2. CHECKLIST FOLLOWED FOR FLAPS 5 SLATS EXTENDED LANDING. FOUND LINT & DIRT IN FLAP BOX AROUND OPTICAL SWITCHES. REMOVED DEBRIS FROM ASSY, REINSTALLED COVER WITH RETAINED HARDWARE. REINSTALLED FLAP HANDLE, OPS CHECKED GOOD. CYCLED SYS SEVERAL TIMES, NO FAULTS NOTED. COMPLETED IAW MM 27-51-00 REV 41.