I didn't have a reverse camera in my Stepwagon, so I fitted a cheap £10 from ebay that uses the usual yellow RCA plug. Obviously, I didn't have the front camera either, so I fitted one there, too, since I found it harder to judge where the front was than the vertical rear, and I was frequently embarrassing myself by straddling parking bays. Anyway, in case anyone has or will have the same head unit as me, or the similar Eclipse AVN-Z01, I've attached a graphic of the key pinouts; I don't think you'll find them easily elsewhere. When the cameras are fitted, the System information screen changes two of the fields on the right to let you know they are present. I believe it senses their presence by the link connecting the ground pins, and the Navi won't switch to a camera input if it hasn't detected the camera on startup. I happened to have an LM2596 DC-DC converter in my spares bin (~£2 off Ebay), so I used that in the 6V line (which is what the standard Eclipse cameras are) to convert it to 12V needed by most aftermarket cameras, so the camera powers on when it is in use, and for one minute afterwards. You ought to check first whether it is needed. My picture was just noise without it, but some 12V cameras might cope with 6V. I also found a very easy route for the cable in my RG1 by pulling off a blanking plate under the scuttle in the passenger-side of the engine bay (below mini wiper blade), and entering through the plastic plenum to the cabin fan. The front camera is switched to by pressing and holding the central hard button on the Navi. This info might also be relevant if you are doing the inverse, and have factory fitted cameras but want to replace the head unit with something more western.