As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ICE PROT TEST IN FLIGHT, RECEIVED A WING ANTI-ICE FAIL MSG. MUST AVOID ICE EVENTS, RETURNED. FOUND COUPLING BETWEEN DUEL TEMP CONTROLLER VLV & Y- DUCT LEAKING. R & R RUBBER COUPLINGS IAW AMM 21-60-01 & ETN EM-21-056. OPERATIONS CHECKED GOOD. OPERATIONS OF WING ANTI-ICE GOOD IAW AMM 30-00-00.