As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN CRUISE, MESSAGE 'SINGLE FMC OPERATION' ON R SCRATCHPAD AND VTK ON R MAP DISPLAY. LNAV / VNAV DISENGAGED ON R A/P. CORRECTED ITSELF BEFORE ANY PILOT INTERVENTION WITHIN FEW MIN. GROUNDED - YES. SYS LOGGED 'FMC-R PRES POS LAT RATE' LAST LEG. FAULT NO LONGER PRESENT. SYS OPS CKS NML PER SAME B737-900AMM 34-61-00. GND VERIFICATION SUCCESSFUL.