As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED LT ANTI-ICE DUCT MESSAGE IN FLIGHT. CREW RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE TROUBLESHOT, R & R THERMAL SWITCHES IN LT INBD L/E DUE TO ERRATIC CONTINUITY AND PERFORMED CHECKS IAW AMM. AIRCRAFT RELEASED FOR SERVICE.