As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DETAILED VISUAL INSPECTION OF #1 ENG LOOP "B" FIRE DETECTION HARNESS MW0316 FOUND CHAFING AT THE 12 O'CLOCK POSITION, NEAR OUTBOARD COWLING HINGE. GROUNDED - YES. REMOVED & REPLACED ENG #1 FAN FIRE DETECTION HARNESS PER B737-800 AMM 26-11-02 ACCOMPLISHED OPS CHECK NORMAL.