As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLIGHT 2586, DURING PREFLIGHT INSPECTION THE CREW REPORTED A BURNING SMELL IN THE CABIN. MAINTENANCE INSPECTED THE AIRCRAFT AND FOUND THE LAV LIGHT BALLAST TO BE CAUSING THE SMELL. MAINTENANCE REMOVED THE AFFECTED LIGHT BALLAST AND PLACED THE AIRCRAFT ON NEF, AND WAS APPROVED FOR RETURN TO SERVICE.