As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN SELECTING THE GEAR DOWN, ONLY THE RIGHT MAIN EXTENDED. RIGHT GREEN B-LIGHT AND ALL DISAGREEMENTS ILLUMINATED. THE ELECTRICAL OVER RIDE PROCEDURE IN THE QRH WAS CONDUCTED, RESULTING IN A SUCCESSFUL EXTENSION. REMOVED & REPLACED RIGHT MAIN GEAR SYSTEM-A PROX SENSOR HARNESS WITH A SERVICEABLE PART PER MM 32-61-01 401. CHECKS NORMAL.