As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A/C RETURNED TO FIELD. CREW REPORTED A LAV SMOKE DETECTION AND ELECTRICAL SMOKE ODOR IN CABIN. MX INSPECTED THE A/C LAV AREA BUT COULD NOT FIND EVIDENCE OF A PROBLEM. MX PERFORMED ENGINE RUNS AND THE ODOR WAS COMING THROUGH THE AIR CONDITIONING SYSTEM. MX REPLACED THE DUCT FILTERS. OP CHECKS GOOD.