As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENG 2 FIRE LOOP B FAULT. FOUND FDU 2WD2 CONNECTOR B CONTACT J IS SHORTING TO GROUND. ISOLATED LOOPS, NO HELP. MOVING ON TO ENG HARNESS. REPLACED NR 2 MOTOR CORE FIRE DETECTOR A+B LOOP. CHECKED EACH NR 2 ENGINE LOOP 'B' DETECTORS. CHECKED NORMAL. CLEANED AND RECONNECTED CONNECTOR 450VT2. FAULT ERASE. TESTED SEVERAL TIMES. CHECKS NORMAL.