As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING ETOPS CHECK OF COCKPIT, FOUND THE CIRCUIT BREAKER BUSS 1, THE DC BUSS INDICATION TRIPPED, P6-4. ACFT GROUNDED. ACCOMPLISHED OPERATIONAL TEST OF DC SYSTEM AND OPS CHECK OK IAW AMM 24-31-00-700-801. NO FAULTS NOTED. ACFT OK FOR SERVICE. ALSO A PERFORMED CIRCUIT BREAKER RESET AND NO FAULTS NOTED IAW AMM 20-60-01-860-801.