As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
L1 WINDOW HEAT AMBER OVERHEAT LIGHT ON ZERO DEGREES, RESET 14 MINUTES TO OVERHEAT AGAIN. FOUND A LOOSE SPARE SENSOR TERMINAL END. REPLACED SAME, CHECKED L1 WINDOW RESISTANCE AND TAP SETTING. VOLTAGE WAS WITHIN LIMITS. REPLACED HEAT CONTROLLER FOR PRECAUTION.