As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 84 - RTF - DURING INITIAL TAKEOFF AND CLIMB, HAD AVIONICS SMOKE ECAM WARNING. CAPTAIN DECLARED AN EMERGENCY AND RETURNED TO PHL. MAINTENANCE FOUND DOOR TO AIR FILTER OPEN. CHANGED FILTER AND SECURED DOOR CLOSED; ALSO REPLACED THE SMOKE DETECTOR FOR PRECAUTIONARY PURPOSES. SMOKE DETECTOR, MPN CG7G0, IS BEING REPLACED ON ATTRITION BY MPN CGDU2000-00.