As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE RIGHT MLG INDICATION WAS UNSAFE WHEN GEAR WAS EXTENDED FOR LANDING AT SAT. NO GREEN LIGHT WAS INDICATED. THE GEAR DID NOT APPEAR TO BE DOWN WHEN VIEWED THROUGH THE GEAR VIEWING PORT. AN EMERGENCY WAS DECLARED AND THE AIRCRAFT LANDED WITHOUT INCIDENT. THE AIRCRAFT HAD TO BE TOWED TO THE GATE. MAINTENANCE REMOVED AND REPLACED THE RT MLG DOWNLOCK ACTUATOR IAW MM 32-32-51. OPERATIONAL CHECKS WERE GOOD AND NO LEAKS WERE NOTED.