What was found
AIRCRAFT RETURNED TO PLATFORM, DUE TO LE FLAPS TRANSIT LIGHT TURNED ON AND TAKEOFF WARNING ACTIVATED. MAINT PERFORMED BITE TO PSEU AND FSEU IAW FIM 32-09 TASK 801 AND FIM 27-51 TASK 801 INDICATING FAIL OF SLAT NR1 SENSOR. FSEU WAS REPLACED BUT FAIL CONTINUED, SO SLAT NR1 SENSOR WAS REPLACED IAW MM 27-88-11, TESTED CORRECT. DURING OVERNIGHT CHECK, LEADING EDGE FLAP/SLAT POSITION INDICATION SYS AND LEADING EDGE FLAP/SLAT PROXIMITY SENSOR WERE TESTED IAW MM 27-88-00-710-801 AND 27-88-11-700-801; CONDITION AND ADJUSTMENT OF SLAT NR1 SENSOR S995 WAS PERFORMED IAW MM 27-88-11 PAGES 413 AND 414, ALL CORRECT.