As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS NOT GROUNDED: DURING THE CLIMB, PASSING FL 210, LEFT FWD EMERGENCY EXIT ECAM MESSAGE. CABIN PRESSURE WAS NORMAL. ECAM EXTINGUISHED AT FL 300. ACCOMPLISHED TSM 52-11-00-810-804-A. FOUND PLASTIC CANON PLUG COVER ON TARGET OF PROXIMITY SENSOR 11WV1 AND REMOVED IT. ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK AND FAULT DISAPPEARED.