As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PERSISTENT ANTI-ICE DUCT WARNING MESSAGE. RH FUSELAGE SHOWED RED ON THE SYNOPTIC PAGE. C/W QRH AND RETURNED TO YUL. *********AIRCRAFT REMOVED FROM SERVICE********* T/S PER MTCM 19-149. REPLACED LOOP A46WK PER AMM 36-21-04. OPS CHECK GOOD.