As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - ON FLIGHT 2186, DURING TAXI HAD INTERMITTENT GEAR WARNING HORN WITH ASSOCIATED RIGHT MAIN GEAR UNSAFE INDICATION. MAINTENANCE REMOVED AND REPLACED RIGHT HAND MAIN LANDING GEAR DOWNLOCK PROX SENSOR. FUNCTIONAL TEST IS GOOD. AIRCRAFT RETURNED TO SERVICE.