As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT WAS RUNNING A FIRE LOOP TEST. DURING FLIGHT, THE LEFT FIRE LOOP FAILED THE TEST. THE AIRCRAFT RETURNED WITH NO FURTHER INCIDENT. MAINTENANCE TIGHTENED THE CANNON PLUG ON AFT FIREWALL. THEN, MAINTENANCE SYSTEM CHECKED IT AND IT WAS FINE. NO PARTS WERE USED, THEREFORE NO TEARDOWN REPORT WILL BE REQUIRED.