As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 3331 - DURING PREFLIGHT, THE LAVATORY SMOKE LIGHT WOULD ILLUMINATE WHEN THE LAV DOOR WAS CLOSED AND LOCKED. MAINTENANCE FOUND THE FLUORESCENT LIGHTS INTERMITTENT CAUSING THE LAV SMOKE LIGHT TO ILLUMINATE. REPLACED THE LAVATORY FLUORESCENT BULBS.