What was found
38A COVE LIGHT OUT. *S/D* IT APPEARS THAT MOISTURE FROM AN IMPROPERLY SHINGLED INSULATION BLANKET DRIPPED ONTO THE LIGHT CONNECTOR CAUSING A SHORT. A SERVICE BULLETIN THAT DISTURBS THE BLANKET IN THIS AND OTHER AREAS MAY HAVE BEEN THE CAUSE. A CALLOUT WAS ISSUED TO INSPECT FOR MOISTURE AND CORRECT ANY INCORRECTLY INSTALLED BLANKETS ON THIS AND ALL POTENTIAL ACFT. ALL PARTS HAVE BEEN SENT TO BOEING FOR FURTHER EVALUATION. UNITED AND BOEING ARE DISCUSSING CORRECTIVE ACTIONS TO PREVENT A REOCCURRENCE.