What was found
DESCENDING ON THE MARNR 7 ARRIVAL, RT SIDE VTK SHOWED ERRONEOUS ERRATIC FLUCTUATIONS FROM 17,000 TO 7,000' AT 7000'. THE RT FMC FAILED AND WE HAD SINGLE FMC AND YELLOW VTK ON FO SIDE FOR APPROX 2 MIN. FMC RESTARTED AND WAS NORMAL FOR REMAINING 10 MINS OF THE FLIGHT. GROUNDED - YES. RT FMC SHOWS LAST 3 FLTS ETHERNET-2 FAULTS. REF B737-900 FIM 34-61 TASK 837, FOUND FAULT CONSIDERED A HARDWARE FAILURE, SHOULD BE REPLACED. REF B737-900 AMM 34-61-02, R & R RT FMC COMPUTER, CROSS LOAD GOOD, OPS NML REF SAME AMM. GROUND VERIFICATION TEST GOOD.