Change the battery and check the i/o board is a flashing light is present or no light to identify the problem ,
Check cables and power supply, cables in all parts of cabinet maybe some loose or broken lines to make contact to power supply
Thank you for buying and Trust to Kidkaos of availing a Marvel Vs. Capcom 2
And leaving this good positive Feedback
And the japanese mvc2 cart sometimes in naomi motherboard has a japanese bios.