As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
APU TREND DATA IS SHOWING AN INCREASE IN OIL USAGE. GROUNDED-YES. FOUND APU OIL COOLER LEAKING. APPROXIMATELY ONE DROP PER MIN. REMOVED AND REPLACED APU OIL COOLER, PER B737-900 AMM 49-91-41. GROUND OPERATIONS CHECK IS GOOD. NO LEAKS AT THIS TIME.