As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BLD/IAD - FLT 4126 - EN ROUTE, CREW REPORTED A PROBLEM WITH THE LEFT ENGINE INLET DEICE BOOT. THEY WERE ALERTED BY AN AMBER CAS MESSAGE DEICE BOOT FAIL. AIRCRAFT DIVERTED TO PIT. AIRCRAFT LANDED WITHOUT FURTHER INCIDENT. PIT MAINTENANCE REPLACED THE LEFT ENGINE INLET DEICE BOOT E.F.C.V. IAW MM 30-22-03, GROUND RUN CHECKED GOOD.