As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER TAKEOFF CREW REPORTED A WINDSHIELD HEAT FAILURE. DUE TO CONVECTIVE ACTIVITY EN ROUTE & FORECAST THE FLIGHT IS RETURNING. LANDING WEIGHT WILL BE BELOW MAXIMUM. RESOLUTION IAW FAULT CODE 30420030AI1, WINDSHIELD HEATER CONTROL REPLACED IAW AMM 30-42-01 PB 401. POWER APPLIED MORE THAN 1/2 HR, NO EICAS MSG. OPERATIONS CHECKED SERVICEABLE.