As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - CREW REPORTED RIGHT PACK FAILED ON TAKEOFF WITH LEFT PACK ON PLACARD. EMERGENCY DECLARED FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED LEFT TEMP CONTROL VALVE. SYSTEM GROUND CHECK NORMAL OPERATION.