As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AFT CABIN FORWARD FACING FLIGHT ATTENDANT REPORTS ODOR COMING FROM OVERHEAD ON TAKEOFF ROLL AND ON APPROACH TO DFW THE SMELL CAME BACK. IT SMELLED LIKE NEW PLASTIC AND EXTENDED TO ROW 19 FROM OVERHEAD. ACCOMPLISHED INITIAL SMOKE ODOR FUME TROUBLESHOOTING CARD 26L00021001. FOUND FAULTY LIGHT BALLAST AT ROW 17 DEF SIDEWALL. REPLACED BALLAST PER AMM 33-21-11.