As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
#1 ENGINE B FIRE LOOP WILL NOT TEST. GROUNDED - YES. ACCOMPLISHED BITE CHECK OF FIRE DETECTION CONTROL MODULE REF B737-800 FIM 26-10 TASK 801. FOUND ENG #1 UPPER FAN B LOOP FAULT RESECURED FAN DETECTION HARNESS MW0316 REF B737-800 FIM 26-10 TASK 805. OPS CHECK OK.