As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - AIRCRAFT ABORTED TAKEOFF WHEN THE CREW RECEIVED A MASTER WARNING FOR TAKEOFF CONFIGURATION ON ROLL. MAINTENANCE REPLACED THE AILERON TRIM ACTUATOR AND CHECKED WIRING IAW COMPLIANCE ORDER 052426. OPERATIONAL CHECK WAS PERFORMED AND THE AIRCRAFT WAS RETURNED TO SERVICE.