As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLT DECK PREFLIGHT BOTH L (SIDE & FWD) WINDOW HEAT OVERHEAT LIGHTS WERE ILLUMINATED. PER QRH TURNED OFF L SIDE & FWD WINDOW HEAT FOR 5 MINS AND THEN TURNED BACK ON. OVERHEAT LIGHTS DID NOT ILLUMINATE UNTIL APPROX 10 MINS LATER. UNABLE TO DUPLICATE FAULT. PRECAUTIONARY REPLACED P5 9 MODULE WINDOW/PITOT HEAT REF MM30 41 41. OPS NORMAL. VERIFICATION FLIGHT SUCCESSFUL.