Hi, I have tomtom go I don't know what go model it is, it just says tomtom go on the device, I do know its an older model, it looks like the tomtom 500, with sd card slot at the bottom of the screen, my problem is it won't charge, no green light, I probably need a new battery but I thought I'll ask you guys first, if I do need a new battery can you please tell me how to replace it, I have looked at the device and cant see any screws at all .