As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU WILL NOT START. RESET CB'S B06, B07 ON P310 PANEL AND 'A03' ON P49 PANEL. NO HELP. INSTALLED NEW BYPASS VALVE SWITCH, NO HELP. CHECKED ACCESSORY CASE MASTER CHIP DETECTOR FOUND LARGE METAL CHUNKS. SUSPECT APU IS SEIZED. REMOVED AND REPLACED APU. OPS CHK GOOD.