As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT DIVERTED TO SJU. WHILE IN CRUISE AT FL 330, 2150Z, SMOKE WAS NOTED COMING FROM F/O SIDE PANEL. EMERGENCY PROCEDURES WERE FOLLOWED AND AN OVERWEIGHT LANDING WAS MADE WITHOUT INCIDENT. TROUBLESHOOTING BY MTX LOCATED A BURNED OUT FLUORESCENT LIGHT BALLAST. BALLAST WAS REMOVED AND REPLACED, SYS OPS CHECKED NORMAL. OVERWEIGHT LANDING INSPECTION REVEALED NO STRUCTURAL DAMAGE.