What was found
DURING DECENT, UPON SELECTING GEAR DOWN. ALL 3 GREEN GEAR DOWN AND LOCKED LIGHTS ILLUMINATED. THE RED GEAR UNSAFE LIGHT ALSO REMAINED ILLUMINATED. AFTER LANDING THE RED UNSAFE LIGHT EXTINGUISHED AFTER SEVERAL MINUTES. CURRENTLY WE HAVE BEEN UNABLE TO DUPLICATE SQUAWK. AFTER 2 DAYS OF TROUBLESHOOTING, STILL UNABLE TO DUPLICATE. REPLACED GEARDOWN RELAY WITH NEW (PN 237- EAU) AND ALL 3 (MAIN AND NOSE) LANDING GEAR DOWNLOCK SWITCHES WITH NEW. ALL GROUND OPS CHECKS AND FLIGHT TEST NORMAL. (SW01200501233) (K)