As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MULTIPE FMC FAILURES. BOTH SINGLE AND DUAL FMC FAILS. OPERATION WOULD BE RESTORED, THEN FAIL AGAIN ON LATER FAILURES. STARTED AS SINGLE (CAPT) FMC FAIL. THEN WHEN FMC SWITCH SELECTED TO BOTH ON 2, THEN DUAL FMC FAIL. FMC OPERATION FOR LAST 30 MINS OF FLIGHT. GROUNDED - YES. RESET NO 1 AND NO 2 FMC'S PER B737-800 FIM 34-61 TASK 836. BOTH FMC'S RESTORED. OK FOR SERVICE.