As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. LIGHTING SYSTEM DISAGREES WITH ECAM MESSAGE. DECLARED AN EMERGENCY PRIOR TO LANDING DUE TO NOSE GEAR STEERING INDICATION. FLIGHT LANDED WITHOUT INCIDENT AND AFTER A RESET, WAS ABLE TO TAXI TO THE GATE UNDER ITS OWN POWER. MAINTENANCE INSTALLED SERVICEABLE LEFT HAND DOWNLOCK SENSOR (15GA) PER A320 AMM 32-31-73.