What was found
DURING VISUAL APPROACH, MLG SELECTED DOWN, MLG DISAGREE RT AMBER CAS ILLUM YELLOW X ON RT MLG INDICATOR. ABORTED APPROACH & RAN QRH, USING BLOWDOWN HANDLE. TOWER VERIFIED THE RT MLG DOWN. FLAP SELECTED TO FULL, RT MAIN INDICATOR TURNED RED & REMAINED. ACFT LANDED SAFELY. JACKED, CONNECTED GPU, CONNECTED HYDAUUC MULE, SERVICED EMERGENCY BLOW DOWN BOTTLE. PERFORMED 10 MLG SWINGS IN ATTEMPT TO DUPLICATE DISCREPANCY, NO FAULTS NOTED. REMOVED RT MLG UPLOCK SWITCH. INSTALLED A NEW UPLOCK SWITCH. PERFORMED 5 MLG SWINGS VERIFID RIGGING OF RT UPLOCK SWITCH. OPS CHECKED GOOD. PERFORMED FULL HYD SYSTEM BLEED. SERVICED HYD SYS. NO DEFECTS NOTED & ALL CHECKED GOOD. WORK DONE IAW AMM 12-10-30 & AMM 32-32-25.