What was found
LE FLAP TRANSIT LIGHT COMING ON WITH RH LE SLAT LIGHT ON OVERH EAD PANEL FSEU BITE FAULTING NO.4 LEADING EDGE FLAP SENSOR, MAINT MSG 27-81223. OVERHEAD SLAT INDICATOR SHOWS GREEN WHEN FLAPS EXTENDED, SHOWS AMBER INTRANSIT INTERMITTENTLY WHEN FULLY RETRACTED. SUSPECT LEADING EDGE FLAP RETRACT SENSOR S00174 AT FAULT. REF WDM 27-81-21-1. TECHSUP UPDATE: FSEU I/O MONITOR INDICATE F4 EXT SENSOR (S00175) FROM MARGINAL TO NEAR ALTERNATLY WITH LE FLAP FULLY RETRACTED. REMOVED AND REPLACED LE FLAP PROXIMITY SENSOR (S175) REF AMM 27-88-11/401.INSTALLATION SENSOR TEST PASSED. NO EXISTING FAULTS ON FSEU.