As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - CREW REPORTED ON CLIMBOUT TAIL COMPARTMENT TEMPERATURE HIGH LIGHT ILLUMINATED. QRH PROCEDURE ACCOMPLISHED AND LIGHT WENT OUT. EMERGENCY DECLARED FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. FOUND DUCT COUPLINGS LEAKING BETWEEN FLOW CONTROL VALVE AND PRIMARY HEAT EXCHANGER ON BOTH PACKS. REPLACED SEALS IN BOTH COUPLINGS. SYSTEM GROUND CHECK NORMAL OPERATION.