Connecting rear camera in car with a switch

[Starway]

Oh bloody hell how did I miss that post, thankyou so much that is great. I think I have finally for this understood 

Very useful thanks 

 

[Starway]

Just wanted to thank everyone who contributed . This world is a better place with you guys in it 

 

[poni]

ust a switch like i posted with 2 power inputs and 1 load. ? Isn’t that the simplest ?    That way I don’t need diodes ?

that's kind of what I said ,but I missed the diode's thought they were fuses , note to self ,"must wear glasses when reading"