As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PHX - CREW REPORTED TAIL COMPARTMENT TEMPERATURE OVERHEAT LIGHT ILLUMINATED IN CLIMBOUT. EMERGENCY DECLARED FLIGHT RETURNED PHX LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. FOUND PNEUMATIC DUCT LEAKING FORWARD OF FLOW CONTROL VALVE. REPLACED CLAMP. SYSTEM GROUND CHECK NORMAL OPERATION.