[encantotom]

there are only 4 wires that are used. one is data +, another is data -, then 12v power and ground

there are two ways to power the usb port, one is from the laptop and the other from the ignition. on some laptops (like mine) it saw that having the laptop power it as well as the ignition switch as a power problem and would shut the laptop off immediately. only some of the newer chipsets do that (i have a new ivy bridge laptop)

if that happens, then you take the lid off of the vmspc and there is a jumper you remove and that only allows it to be powered one way and walla, it worked fine.

tom