What was found
RETURNTED TO GATE. APU ENGINE CONTROL UNIT CAUTION MESSAGE. MAINTENANCE REMOVED AND REPLACED APU ENGINE CONTROL UNIT. OPERATIONAL TEST GOOD. AIRCRAFT RETURNED TO SERVICE.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
RETURNTED TO GATE. APU ENGINE CONTROL UNIT CAUTION MESSAGE. MAINTENANCE REMOVED AND REPLACED APU ENGINE CONTROL UNIT. OPERATIONAL TEST GOOD. AIRCRAFT RETURNED TO SERVICE.