As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE NRT TO SPN AT THE HALFWAY POINT, PILOTS REPORTED ELECTRICAL SHORT AND FUMES FROM FIRST OFFICERS ADI. PULLED CIRCUIT BREAKER AND SHORT AND FUMES STOPPED. PILOTS DID NOT DECLARE AN EMERGENCY. MAINTENANCE PERFORMED WIRING CHECKS AND REPLACED THE ADI. ALL CHECKS WERE GOOD.