As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LH SIDE OVERHEAT (ONAPP) RAN CHECKLIST AND OVERHEAT STAYED ILLUMINATED. GROUNDED - YES. REMOVED AND REPLACED THE L-2 WINDOW AND ADJUSTED TO WITHIN LIMITS REF B737-900 AMM 56-12-11/401 AND 56-12-11-820-801. WINDOW HEAT SYSTEM OPERATIONAL TEST PASS. LEAK CHECK OF THE L-2 WINDOW PASS.