As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT & RIGHT WING ANTI-ICE CAUTION MESSAGES IN ICING CONDITIONS, C/W QRH, LEFT ICING & RAN ICE DISPERSAL PROCEDURES. MESSAGE CLEARED FOR 2 MINS THEN RETURNS. ANTI-ICE WAS SELECTED TO NORMAL, OPENED ISOLATION VALVE, MESSAGE REMAINED. WENT TO STBY, MESSAGE CLEARED TEMPORARILY. BOTH WINGS SHOWED YELLOW ON EICAS THEN WENT CLEAR. BOTH SOVS INDICATED OPEN. NO DUCT FAIL LIGHT OR DUCT WARNING MESSAGE. WING ANTI-ICE ON MESSAGE WENT AWAY WHEN CAUTION APPEARED. AIRCRAFT REMOVED FROM SERVICE. R & R THE LT AND RT PRESSURE SWITCHES.