As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW IDENTIFIED THE WINDSCREEN OVERHEAT ANNUNCIATOR CAME ON AT TAKEOFF POWER WITH VALVES CLOSED AND SWITCH OFF. THE CREW ABORTED TAKEOFF AND MAINT WAS CALLED IN. TROUBLESHOT ACFT WINDSHIELD HEAT SYS IAW MM, NO DEFECTS NOTED. ENGINE RUN AT FULL POWER, NO BLEED AIR DETECTED ACROSS WINDSCREEN. ALL CHECKS WERE NORMAL, COULD NOT DUPLICATE.