As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI OUT OBSERVED VTK ON CAPTAIN'S ND AND MAP ON F/O'S ND. AFTER STOPPING CAPTAIN'S ND WENT BACK TO NORMAL BUT F/O ND REMAINED WITH MAP ANNUNCIATED. PERFORMED QRH FOR FMC FAIL, ALL DISPLAYS AND BOTH FMC WERE RESTORED TO NORMAL. ACFT GROUNDED. COMPLIED WITH TASK CARD 78273000, INTERROGATE THE FMC CDU FOR ENGINE FAULTS. NO DEFECTS NOTED.