As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - FLT 4401 - DURING CLIMB, CREW REPORTED THE LAV SMOKE CAUTION LIGHT ILLUMINATED. AIRCRAFT RETURNED TO ORD, LIGHT EXTINGUISHED DURING APPROACH. MAINTENANCE COULD NOT DUPLICATE DISCREPANCY. OPS CHECK WAS GOOD AND AIRCRAFT WAS RELEASED FOR FLIGHT. NEXT FLIGHT SAME DISCREPANCY. MAINTENANCE THEN REPLACED LAV COMPARTMENT SMOKE DETECTOR. OPS CHECK WAS GOOD AND AIRCRAFT WAS RETURNED TO SERVICE. (M)