As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: APU AUTO SHUTDOWN 23 MINUTES AFTER TAKEOFF. APU SHUTDOWN AGAIN AFTER RESTART. RETURNED TO DFW, LANDING SAFELY. REPLACED APU LOW OIL PRESSURE SWITCH (AALA202205110105) PER AMM 49-94-14. OPERATIONAL AND LEAK CHECKS GOOD. REPLACED #2 EGT THERMOCOUPLE PROBE (AALA202205127356) PER AMM 49-72-15. OPERATIONAL CHECK GOOD.