As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"VTK" APPEARED IN FO'S NAV DISPLAY, AND POS SHIFT PAGE ON MCDU INDICATES BLANK SPOT UNDER FMC-R. AFTER TWO MINUTES, FMC RESTORED AND "VTK" DISAPPEARED FLIGHT LEVEL 350 PHKO - KSEA. GROUNDED - YES. FMC-R LOGGED "WATCHDOG TIMER" AS INFLIGHT FAULT ACCOMPLISHED FMC BITE REF B737-900 FIM 34-61 TASK 801 WITH NO CURRENT FAULTS.