As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE CLIMB WE RECEIVED AN ''ANTI-ICE DUCT'' WARNING MESSAGE WHICH WOULD NOT EXTINGUISH WHILE ANTI-ICE WAS ON. ANTI-ICE SYNOPTIC PAGE SHOWED LEFT WING ANTI-ICE DUCT ILLUMINATED IN RED. REMOVED AND REPLACED SENSOR.IAW AMM 30-12-00. PERFORMED ENGINE RUNS FOR OPS CHECK. OPS CHECKS GOOD AT THIS TIME.