As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - FLIGHT 353 - AIRCRAFT RETURNED TO FIELD WHEN AFTER TAKEOFF THE RIGHT MAIN GEAR SHOWED UNSAFE AND THE LIGHT IN HANDLE STAYED ON WHEN THE GEAR WAS RETRACTED. MAINTENANCE INSPECTED THE AIRCRAFT AND REPLACED THE RIGHT GEAR DOOR CLOSED PROXIMITY SENSOR AND ADJUSTED THE LEFT DOOR CLOSED PROXIMITY SENSOR. OPERATIONAL CHECKS WERE PERFORMED AND CHECKED GOOD. AIRCRAFT RETURNED TO SERVICE.