As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT OUTBOARD WINDOW OVERHEAT LIGHT ILLUMINATED DURING FLIGHT, EXTINGUISHED WHEN CYCLED OFF. GROUNDED - YES. CHECKED THE ELECTRICAL RESISTANCE OF THE WINDOW HEAT FILM REF B737-900 AMM 30-41-21-000-801. RESISTANCE READS 60.7 OHMS ON TAP #2 OF TB5016. THIS DESIGNATES AN H16 WINDOW, AND THE INSTALLED IS MARKED H15. MOVED TAP ACCORDINGLY FROM #2 TO #1. ACCOMPLISHED WHCU BITE REF FIM 30-41 TASK 801. OPS CK GOOD.