I would start with checking the wiring and the DC-DC PCB. I attached a wiring diagram for the D70 that might give you a starting point to check for power with a multimeter. I do have the D70-S repair manual right here.Do feel free to download it and see if it helps you to narrow down your problem. Apparently there is not much difference between the D70 and the D70s with the exception of a bigger LCD and some minor cosmetic changes. Some more info on that right here I would think that most of the wiring and instructions are the same. Good Luck