As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLIGHT 2414 - DURING PREFLIGHT INSPECTION THE CREW REPORTED A BURNING SMELL IN ROW 1. MAINTENANCE REMOVED AND REPLACED THE LIGHTING BALLAST ABOVE ROW 1, OPERATIONALLY TESTED WITH NO DEFECTS, AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.