As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EICAS MESSAGE "NR 1 ENG FIRE LP1" DISPLAYED. TESTED NR 1 ENG FIRE DETECTION SYS PER MM 26-11-00-501 AND 26-11-00-0101. ALL CHECKED GOOD ON GROUND. CANNOT DUPLICATE PROBLEM. INSPECTED NR 1 ENG FIRE LOOPS, ALL LOOKS GOOD. NO DEFECTS FOUND.