As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX-RETURNED TO FIELD FOR NR 1 RUDDER HYDRAULIC, RUDDER FULL PRESSURE AND RUDDER PRESSURE CAUTION LIGHTS. HYDRAULIC PRESSURE WAS NORMAL. AIRCRAFT LANDED WITHOUT INCIDENT. REMOVED AND REPLACED RUDDER PRESSURE REGULATOR AND ISOLATION. OPERATIONAL CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.