As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTS #2 ENG FIRE DETECTION LOOP B IS INOP. GROUNDED - YES. TROUBLESHOT PER B737-800 FIM 26-10 TASK 805, FOUND BAD TERMINAL CONNECTION AT M1760 (RIGHT AFT UPPER CORE LOOP B). REPLACED WIRE HARNESS MW0326 (P/N 325-027-606-0) PER B737-800 AMM 26-11-02 PG# 401, SYSTEM OPS CHECKED GOOD. ETOPS GROUND VERIFICATION SUCCESSFUL.