As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENROUTE WHILE DESCENDING, SELECTED ENGINE ANTI-ICE ON. RECEIVED A LEVEL 1 NR 2 ENGINE. ANTI ICE DUCT FAILED MESSAGE. RETURNED TO DEPARTURE. COMPLIED WITH FIM, INSPECTED ANTI-ICE DUCT AND FOUND NO EVIDENCE OF LEAK. CHECKED ANTI-ICE SENSOR RESISTANCE AND FOUND VALUE BELOW LIMITS.