What was found
ON APPROACH TO LAND, LOWERED LANDING GEAR AND DID NOT GET DOWN AND LOCKED ON ANY GEAR JUST 3 RED INDICATIONS. GRABBED GEAR HANDLE AND CHECKED FOR LOCKED DOWN HANDLE, THEN JIGGLE HANDLE, NO HELP. CYCLED LANDING GEAR AND AGAIN GOT 3 RED INDICATIONS. HYDRAULICS WERE GOOD, CHECKED HANDLE FOR SECURITY AND STILL NO GREEN LIGHTS (EITHER SD OR LIGHTS). HIT THE HANDLE HARD WITH FIST AND INSTANTLY GOT 3 GREEN INDICATION. REMOVED AND REPLACED S1-431 LANDING GEAR HANDLE SWITCH, OPS CHECKS OK PER MM 32-31-02-2 AND SUPP 32-60-00-0 PAR 11.