As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - ON FLIGHT 2230, TAKEOFF WARNING HORN SOUNDED DURING TAKEOFF, CONFIGURATION TEST ON TAXI OUT. CHECKED CONFIGURATION AND HORN STILL SOUNDED. MAINTENANCE ADJUSTED CONDITION LEVER LIMIT SWITCHES. PERFORMED FUNCTIONAL TEST OF THE TAKEOFF WARNING HORN, FUNCTIONAL TEST GOOD. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.