As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ASH 7452 ABE - CAPTAIN REPORTED APU FIRE INDICATION ON APPROACH FOR 2 OR 3 SECONDS DURING APU START UP, FOLLOWED BY APU FAIL THEN APU DOOR INHIBIT. MX INSPECTED AND NO FIRE OCCURRED DURING APU START. MX R & R THE GASKET ON THE FUEL NOZZLE AND TIGHTENED THE SUPPLY LINE TO THE FLOW DIVIDER. OP'S CHECK GOOD.