As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT CREW REPORTED LT ENG FIRE DETECTION LOOP A FAILED IN FLIGHT, QRH PERFORMED. MAINTENANCE PERSONNEL VERIFIED GOOD RESISTANCE D-V AT LT FIRE DETECTION UNIT CONNECTOR. 465 OHMS, NO CHAFING AND OBIVIOUS DEFECTS ON ENGINE, SYSTEM OPS CHECKS GOOD IAW AMM 26-10-04 AND 26-10-00 OF FOR SERVICE.