I have a v950str that I bought last year from WalMart. (yes I know I am a complete amateur!). But I went to get it going this year and I cant get any motor function. I have 3.99v at the battery (only a 3.7v). The green lights flash untill I turn on the controller then they steady along with the light on the controller. Any ideas would be great! I would like to beat on this one a little more before I spend allot on a good one. Thank you