As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT THE LAV AT DOOR 3 LEFT A PASSENGER NOTICED THAT THE LIGHTS FLICKERED AND WENT OUT. THIS WAS FOLLOWED BY SOME SMOKE FROM OVERHEAD THE SMELL OF BURNING PLASTIC. FLIGHT CONTINUED ON AND LANDING WAS UNEVENTFUL. MAINTENANCE REMOVED AND REPLACED LAV BALLAST. OPERATIONAL CHECKED GOOD AND AIRCRAFT WAS RETURNED TO SERVICE.