What was found
FLAPS FAILED IN FULL DOWN POSITION. TROUBLESHOOTING FOUND POWER AT BOTH UP AND DOWN PINS OF FLAP CONTROL VALVE. FOUND RT FLAP (19 DEGREES/21 DEGREES) LIMIT MICROSWITCH MAINTAINED CONTINUITY IN ALL SWITCH LINKAGE POSITIONS. REPLACED SWITCH AND SYSTEM OPERATED NORMALLY. AIRCRAFT RETURNED TO SERVICE. NOTE: LEFT LIMIT SWITCH PREVIOUSLY REPLACED WHEN FLAPS FAILED AT 8 DEGREES. BOTH SWITCHES WERE INSTALLED IN DECEMBER, 1994. LEFT SWITCH TT 35 HOURS/RT SWITCH TT 48 HOURS.