What was found
DURING CLIMBOUT, THE MAIN LANDING GEAR DOOR OPEN LIGHT REMAINED ILLUMINATED. THE FLIGHT CREW FOLLOWED COM PROCEDURES, RETURNED TO ORIGINATION, AND LANDED WITHOUT INCIDENT. LANDING GEAR DOOR OPEN LIGHT EXTINGUISHED ONCE MAIN LANDING GEAR WAS IN THE DOWN AND LOCKED POSITION. MAINTENANCE REPLACED THE LEFT AND RIGHT MAIN LANDING GEAR UPLOCK SWITCHES, OPERATIONAL CHECK OK.