As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU CT5ATP EGT TREND DATA SHOWS EGT HAS SHIFTED ABOVE THE MAINTENANCE THRESHOLD OF 593 BUT LESS THAN 605 DEGREES. ETOPS SIGNIFICANT SYSTEM. ACFT GROUNDED. REMOVED AND REPLACED THE APU FUEL NOZZLES AND SHROUDS. OPS AND LEAK CHECKED GOOD IAW AMM 49-31-14. REMOVED AND REPLACED THE APU EGT THERMOCOUPLES. OPS AND LEAK CHECKED GOOD IAW AMM 49-71-21.