If you can roll it over by hand, try and start it without the plugs in, but make sure you ground the plug wires on the grounding studs. See if anything comes out when you turn it over.
Also, what is the the background, was it running good and just stopped, it is a new to you ski and you don't know its history. Sometimes lettings us know what it was doing before it stopped can help diagnose things.
Whatever you do don't use a jump pack o try jumping it with jumper cables, it will fry the electronics!