As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN CRUISE OBSERVED "VTK" AND "LDG ALT" FLAG ON FIRST OFFICERS SIDE. ALONG WITH LOSS OF LNAV AND VNAV, CONSIST WITH RIGHT FMC FAILURE. ALERTS CLEARED BEFORE COMPLETING THE QRH CHECKLIST. GROUNDED - YES. ACCOMPLISHED B737-900 FIM 34-61 TASK 836. NO HARDWARE FAULTS; INTERMITTENT CONDITION. OPS TEST GOOD. GROUND VERIFICATIONS TEST GOOD.