As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW TAIL COMPARTMENT TEMPERATURE HIGH LIGHT ILLUMINATED. ACCOMPLISHED QRH PROCEDURES & LIGHT WENT OUT. EMERGENCY DECLARED FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED LEAKING GROUND AIR CONDITIONING CHECK VALVE. SYSTEM GROUND CHECKED NORMAL OPERATION CLOSED.