OK, that pack has very little power, especiall for a tamiya tank running a DMD and MFU. I am not saying it won't work, just that you will have little run time with it. I suggest recharging it and trying the tank again. If this does not work, let us know and we can go further, but I think this is your trouble. Try to get yourself a good pack. Maybe 3800 or over mHA. You can fund deals on ebay or search allbatterypack.com. Let me know if the recharge helps.