As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 1 ENGINE FIRE CAME ON INTERMITTENTLY DURING FLIGHT WITH BLEED AIR ON FIRE WARNING TEST OK. TIGHTENED LOOSE LINE TO PRBC ON NR 1 ENGINE. RAN ENGINE AT VARIOUS POWER SETTING WITH BLEED ON, NO LEAKS NOTED. NO FIRE WARNING, OPS CHECK NORMAL.