Question about using diodes

[MyDaughters20JL]

I can tinker just fine, but I'd prefer to have knowledge before definitely deciding whether to tap into reverse wires or use diodes & wire to aux switch and reverse wires.

I've wired up plenty of things on vehicles, but never with diodes

in the following diodes, are they wired such that the reverse light of the vehicle and the wire from the switch compose the 2 "in" and a wire from the out to the aux light?

Sponsored

 

[Deke]

You sound like you have it right. The "In" side are the two potential sources of 12v power, the "Out" side is the load you want to power with 12v (Aux light)