As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"SINGLE FMC" AND FO'S DISPLAY IN MAP MODE ( R FMC INOP ). LOSS OF LNAV AND VNAV. DURING CRUISE. CORRECTED ITSELF AFTER 30 SEC WORKED FINE FOR REMAINDER OF FLIGHT. GROUNDED - YES. REMOVED AND REPLACED FMC #2 IAW B737-800 AMM 34-61-02. PERFORMED OPERATIONAL TEST OF R FMC IAW AMM 34-61-00. OPS CHK GOOD.