What was found
AIRCRAFT WAS GROUNDED: LE FLAPS TRANSIT AMBER LIGHT ILLUMINATED UPON SELECTION OF 30 FLAPS. COMPLETED QRH PROCEDURE AND LANDED AT FLAPS 15 WITH GREEN LE FLAPS LIGHT. ON CLEAN-UP, LE FLAPS TRANSIT AMBER LIGHT CAME BACK ON. VISUAL CONFIRMATION OF SLATS PARTIALLY EXTENDED THROUGHOUT. MAINTENANCE ACCOMPLISHED FIM TASK 27-81-00-810-892. RESET FLAP / SLAT SYS B HYD FUSES IAW AMM 27-81-61. SLATS / FLAPS RETRACT & EXTEND AS NORMAL.