What was found
AFTER LANDING, INTERMITTENT "VTK" ON NR 1 FMC, WHEN PRESSING "INIT REF" GET AN INTERMITTENT "FMC" PROMPT ON LSK L1, AND WHEN FMC IS SELECTED, THE SCREEN REVERTS BACK TO MENU IN 10-15 SECONDS. ACFT GROUNDED. COULD NOT DUPLICATE MALFUNCTION. NO FLIGHT FAULTS WERE LOGGED FOR EITHER FMC. DISCREPANCY MEETS CRITERIA FOR "FLIGHT OPERATIONS NORMAL-YET-NUISANCE CONDITION FOR AIRCRAFT WITH FMC OPS U11.0 SOFTWARE INSTALLED." REF B737-900 AMM 34-61-00-860-801. LEFT & RIGHT FMC OPS CHECK NORMAL, REF B737-900 AMM 34-61-00-710-801.