As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - ON CLIMBOUT AUTO PRESSURIZATION CONTROLLER NUMBER 2 FAILED. NUMBER 1 CONTROLLER ON PLACARD. FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED THE NUMBER 1 CONTROLLER DUE TO VALVE MOTOR FAULT NOT CLEARING. SYSTEM GROUND CHECKED NORMAL OPERATION.