There's usually a large label inside the UDC or on the inside of the hatch door. But if not, here's a diagram that probably matches your setup.
However, it's pretty easy for the factory to make a mistake when connecting the wires to the back of the UDC. So if you make the connection and don't get results, try the others. Also, inspect the coax connectors for stray ground wires shorting the connection and for loose connectors.