As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: CABIN PRESSURE SYSTEM 2 FAULT, AIRCRAFT RETURNED DFW WHERE IT LANDED SAFELY WITHOUT FURTHER INCIDENT. (NO EMERGENCY WAS DECLARED). MAINTENANCE REPLACED #2 CABIN PRESSURE CONTROLLER AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 21-31-34 AND 21-31-00.