What was found
LANDING GEAR HANDLE WOULD NOT MOVE TO THE UP POSITION. COMPLETED ABNORMAL PROCEDURE AND GEAR HANDLE OPERATED NORMALLY. SWITCHED TO SYSTEM 1. PERFORMED OPS CHECK OF GEAR PROXIMITY UNIT REVEALED FAULT AT B12; SLAVED IN NLG SENSOR, NO HELP. RESTORED ORIGINAL. REPLACED PROXIMITY DETECTOR UNIT IAW M/M 32-61-12. OPS CHECKED, NO FAULTS FOUND.