As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT FWD WINDOW HEAT DISPLAYED OVERHEAT CLIMBING THROUGH FL 260. QRH PROCEDURE DID NOT CLEAR. CAPTAIN ALSO WITNESSED ELECTRICAL ARCING ON POWER STRIP IN GLASS. R & R WHCU M321 PER B737 AMM 30-41. R/R #1 WINDOW PER B737 AMM 56-11. OPS CK LK CK GOOD. (9463784) AIRCRAFT WAS GROUNDED