As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ABOUT 500' AFTER TAKEOFF 'LAV SMOKE' WARNING ILLUMINATED. WARNING LIGHT WENT OFF ON FINAL APPROACH, FA REPORTED SMOKE IN CABIN. TOUCHDOWN WAS SOFT. REMOVE AND REPLACED BOTH LAVATORY BALLAST IAW 140 AMM 33-28-02. OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.