As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU UNABLE TO START AFTER THREE ATTEMPTS. LOW OIL PRESSURE LIGHT ILLUMINATED FOLLOWED BY FAULT LIGHT ON EACH ATTEMPT. REPLACED APU STARTER GENERATOR UNIT IAW AMM 49-41-21 AND APU STARTER POWER UNIT IAW AMM 49-41-41. APU GROUND VERIFICATION TESTS PASS.