As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE WE RECEIVED AN FMC DISAGREE MESSAGE. MESSAGE WENT AWAY WITHIN SECONDS. DURING SHUTDOWN WE RECEIVED THE SAME MESSAGE AND AGAIN IT WENT AWAY WITHIN SECONDS. GROUNDED - YES. ACCOMPLISHED FMC BITE PER B737-900ER FIM 34-61 TASK 801. NO FAULTS LOGGED. A/C OK FOR SERVICE.