As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT SIDE WINDOW OVERHEAT LIGHT ILLUMINATED AT CRUISE EXTINGUISHED AFTER PERFORMING CHECKLIST. GROUNDED - YES. AS PRECAUTION RECYCLED AIRCRAFT POWER, RAN WINDOW HEAT SYSTEM OPS CHECK REF B737-900 AMM 30-41-00 SYSTEM OP CHECKS GOOD NO DEFECTS NOTED GROUND VERIFICATION NORMAL.