As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SHORTLY AFTER LEVELING OFF AT FL350, CAPTAINS NAV DISPLAY MAP WENT BLANK WITH "VTK" INDICATED (LOSS OF LEFT FMC) ABOUT 30 SECONDS LATER FMC RECOVERD ON ITS OWN AND RETURNED TO NORMLA OPERATION. CAPTAINS MAP DISPLAY RETURNED TO NORMAL. GROUNDED - YES. PERFORMED FIM 34-61 TASK 801 FMC BITE SHOWS NO FAULTS.