3 in 1 out

I know how to wire 1 in 3 out as if we are wiring for extra accessories. I need help with 3 in 1 out, opposite. my 7" head unit has one video input which already occupied by the rearview camera. I want to hook up more camera to sideview mirror like in the Hondas. do we use the same relay as one we use for 1 in 3 out? yes I went to the Replay sticky page didn't see what I was looking for unless it was worded differently.Dont Drive and Text, but

Do Text Then Drive

Post the relay diagram for the one to three. It may work. If not, I'll draw a diagram with two relays and a three position toggle switch as soon as I can get to my computer. the12volt • Support the12volt.com

Depending on how much work he wants to do, and how much money he is willing to spend, it can all be done automatically without the switch. It will take 2 of these: https://www.the12volt.com/relays/page5.asp#pts As well as 3 more relays and several diodes. And we need to know which will take priority, Reverse or left and right. If left and right are priority you will be able to put blinker on to see either side while backing up. Backing up with no blinker will show backup, then if you want to get a look left or right turn on that blinker till you see what you need to see, then blinker off and it will switch back to the backup. It will be a bit of a project for you but if you are going to do it we will put together a diagram for you. Previous offer for a diagram using a switch will only take 3 relays a single switch and a few diodes. A much easier solution. Let us know which way you want to go.