As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
VOLTAGE REGULATOR FAILURE IN FLIGHT RESULTED IN OVERVOLTAGE CONDITION. CAUSED BATTERY OVERHEATING/SWELLING AND COMMUNICATION RADIO FAILURE. NO FIRE OR SMOKE NOTED. PART INSTALLED PER AIRCRAFT MAINTENANCE MANUAL. AIRCRAFT LANDED SAFELY WITH LOSS OF COMMUNICATIONS.