As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
L SIDE WINDOW OVERHEAT IN FLIGHT RAN QRH, OVERHEAT LIGHT STAYED ILLUMINATED. SWITCH LEFT IN OFF POSITION FOR REST OF FLIGHT. GROUNDED - YES. FOUND L2 WHCU SENSOR FAULT. SWAPPED TO SPARE SENSOR OP CK GOOD REF B737-800 FIM 38-41 TASK 811.