As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN STARTING THE LEFT ENGINE THE LEFT FIRE WARNING OCCURRED. FIRE WARNING STOPPED WHEN ENGINE FUEL CONTROL WAS PLACED TO 'CUTOFF'. AIRCRAFT RETURNED TO THE GATE. MAINTENANCE REPLACED THE LEFT ENGINE CORE UPPER AND LOWER FIRE DETECTORS. OPERATIONAL CHECK OK.