Is the VSS wire on the D3 an analog or digital input? (my '08Audi A4 has an analog output from the vehicle, I believe) Also, is the reverse signal just +12v or nothing - i.e. on or off? Same question for illumination. Reason I'm asking is because I don't want to have to buy another CAN BUS adapter just for these wires (which I do want to hook up).