As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU HAD SHUTDOWN, FAULT LIGHT ILLUMINATED AND EICAS MESSAGE. APU FAULT DISPLAYED. THREE FAILED START ATTEMPTS ALL HUNG AT 25 PCT RPM BEFORE AUTO ABORT. FOUND NO SPARK ON APU ENGINE START, REPLACED EXCITER BOX AND LEAD, OPS CHECKED GOOD.