As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE TOILET CAUTION MESSAGE ON FINAL APPROACH. FA REPORTED LAV SMOKE ALARM WAS GOING OFF. THERE WAS AN ASSOCIATED BURNING SMELL. CAUTION MESSAGE, ALARM AND SCENT ALL DISAPPEARED ON THEIR OWN AFTER ABOUT 1-2 MINUTES. FLIGHT 3569. REMOVED AND REPLACED THE RT ACM DUE TO OIL CONTAMINATION, FOUND DURING TROUBLESHOOTING.