As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTS LEFT FMC WOULD NOT LOAD PERFORMANCE FIGURES. GROUNDED - YES. ACCOMPLISHED BITE OF BOTH FMC'S REF B737-800 FIM 34-61 TASK 801 ON GND & FLT 1 L FMC HAD FAULT, ACCOMPLISHED SENSOR TEST ALL FMC SENSORS STATUS GOOD. ACCOMPLISHED RESET OPENED RESET P18-2 A6 C/B AND RE-ACCOMPLISHED FMC BITE WITH NO FAULTS LOGGED, GND TESTS GOOD.