As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTS EICAS MESSAGE FOR WING ANTI-ICE THREE HOURS AFTER DEPARTURE. RETURNED TO IAD. *S/D* REPLACED AIRFOIL AND COWL ICE PROTECTION SYSTEM CARD, PASSED TEST. PROBLEM REOCCURRED SEVERAL FLIGHTS LATER. REPLACED POWER SUPPLY UNIT LINEAR MONITOR A3 PER AMM 31-09-01 AND LEFT ARINC SIGNAL GATE (ASG) CARD PER AMM 31-09-02.