As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PREFLIGHT OVERHEAT LIGHT FOR LEFT SIDE FWD WINDOW ILLUMINATED FOLLOWED QRH IT ILLUMINATED AGAIN. GROUNDED - YES. FOUND L/H FWD WINDOW HEAT PWR C/B OPENED ON PG-11 GVI C/B WINDOW AND ACCESSIBLE WIRING NO DEFECTS NOTIED RESET C/B REF B737-800 AMM 20-60-01-860-801, L/H FWD HEAT TEST OK REF AMM 30-41-00-710-801.