As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTOPILOT A WILL NOT ENGAGE. GROUNDED - YES. DFCS A F.F.R. SHOWED FOUND FAULT LOGGED ON ONLY 1 FLT LEG. PERFORMED B737-900 FIM 22-13 TASK 804, INITIAL EVALUATION TEST, AILERON TEST 20.31 GOOD NUMEROUS TIMES. PERFORMED LAND VERIFY BITE #49 , PASS WITH NO FAULTS.