As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - (REPEAT ITEM) CREW NOTICED SMOKE AROUND THE HYDRAULIC CONTROL PANEL AND TRAFFIC ALERT AND COLLISION AVOIDANCE SYSTEM WAS INOPERATIVE DURING CLIMBOUT. EMERGENCY DECLARED FLIGHT RETURNED DFW LANDED WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED TCAS DISPLAY. SYSTEM GROUND CHECK NORMAL OPERATION.