As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WINDSHIELD O'HEAT ANNUNCIATOR CAME ON IN FLIGHT WHILE WINDSHIELD HEAT WAS ON, -20ºC RAT. ANNUNCIATOR DID NOT EXTINGUISH AUTOMATICALLY AND WAS ACCOMPANIED BY BURNING ODOR. BOTH WERE RESOLVED WHEN WINDSHIELD HEAT WAS TURNED OFF. REPLACED TEMPERATURE CONTROL VALVE WITH OVERHAULED UNIT, OPS CHECK NORMAL. WORK PERFORMED IAW MM CHAPTER 30-41-02.