As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT CREW REPORTED LT ENGINE FIRE DETECTION FAIL LIGHT CAME ON JUST PRIOR TO ROTATION, THEN FIRE WARNING CAME ON AT 1,500 FEET DURING CLIMB. STAYED ON AFTER DISCHARGING BOTH FIRE BOTTLES. RETURNED TO BASE, AFTER LANDING, APPEARED TO BE NO FIRE. FOUND LT ENGINE PYLON FIRE LOOP BAD AND LT ENGINE CORE FIRE LOOP BAD. REPLACED IAW M/M. PERFORMED FIRE DETECTION SYSTEM OP'S CHECK, NO DEFECTS NOTED