As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE APU FIRE WARNING ACTIVATED DURING APU START WHILE ON FINAL APPROACH TO IAH. THE APU FIRE BOTTLE WAS DISCHARGED AND THE AIRCRAFT LANDED WITHOUT INCIDENT AND TAXIED TO THE GATE. THE APU WAS REMOVED AND REPLACED. LEAK AND OPERATIONAL CHECKS WERE GOOD IAW MM 49-11-00, PAGE 201 AND PAGE 501. THE APU FIRE BOTTLE WAS REMOVED AND REPLACED IAW MM 26-22-11.