As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 3 FIRE DETECTOR LOOP-B SYSTEM FAILED TO TEST. TRANSFERRED TO DMI 12964 CAT-C IAW MEL 26-2-3, PLACARDS INSTALLED. REF DMI 12964 NR 3 FIRE DETECTOR LOOP-B SYSTEM FAILED TO TEST. REPLACED DEFECTIVE CONNECTOR AT FAN CASE RT PER DACO M/M 20-504. OPS CHECKED SERVICEABLE PER DACO M/M 26-10-1. DMI 12964 CLEARED. PLACARD REMOVED.