As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT SIDE WINDOW "OVERHEAT" ILLUMINATED ON APPROACH. RESET VIA QRH AND WINDOW OVERHEAT ILLUMINATED AGAIN. GROUNDED - YES. PERFORMED MULTIPLE GOOD OPS TESTS OF WINDOW HEAT ON L/H SIDE WINDOW PER B737-900 AMM 30-41-00-710-801. PERFORMED GOOD RESISTANCE CHECK OF BOTH SENSORS ON L/H SIDE WINDOW PER AMM 30-41-21-760-801. PERFORMED GOOD OPS TEST OF WINDOW HEAT CONTROL UNIT PER AMM 30-41-11-710-801. NO HISTORY PAST 30 DAYS. COULD NOT DUPLICATE PROBLEM.