As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTOTHROTTLE WILL NOT STAY ENGAGED. GROUNDED - YES. ACCOMPLISHED AUTOTHROTTLE BITE PER B737-900 FIM 22-31 TASK 801, CURRENT STATUS, HAS NO FAULTS. IN-FLIGHT FAULTS SHOWS ASM-2 MSG 22-31688 NUMEROUS TIMES ON LEG 4 ONLY. ACCOMPLISHED FIM 22-32-TASK 819 INITIAL EVALUATION AUTO THROTTLE SYSTEM SERVO MOTORS TEST PASSED WITH NO FAULTS. AUTOTHROTTLE SYSTEM IS OPERATING NORMALLY.