As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ELECTRICAL FUMES SMELT DURING CRUISE FLIGHT. AIRCRAFT RETURNED TO BASE WITHOUT INCIDENT. AFTER TROUBLESHOOTING WAS COMPLETED IT WAS DISCOVERED THAT THE SEARCHLIGHT OVERHEATED AND STARTED TO MELT THE PLASTIC COVER. THE SYSTEM WAS DEACTIVATED AND DEFERRED.