As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GROUND SERVICE REPORTED ARCING AT GROUND EXTERNAL POWER PANEL. CREW REPORTS T/R UNIT 1 LIGHT ILLUMINATED. GROUNDED - YES. FOUND MULTIPLE C/B'S OUT ON P-91 AND P-92 PANELS. ACCOMPLISHED C/B RESET PROCEDURE REF AMM TASK 20-60-01-860-801. NO DEFECTS FOUND. ACCOMPLISHED FIM 24-31 TASK 826. ALL TEST PASED T/R 1 LIGHT EXTINGUISHED ACFT OK FOR SERVICE.