As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TEMPORARILY LOST BOTH NAV DISPLAYS WITH VTK APPEARING ON BOTH NAV DISPLAY SCREENS AND FMC BLANKING / DEFAULTING TO MENU MODE. SYSTEM SELF-CORRECTED IN 40-60 SECONDS. ALL NORMAL. GROUNDED - YES. VERIFIED OPERATION OF FMC NORMAL REF B737-9 AMM 34-61-00-710-801.