Here's where I'm at right now based on the valuable suggestions from
@slomatt and
@MrRob.
I did the switch a little differently so that the majority of the time the relays aren't energized. They are only activated at the need to override the trailer switches. I'm also trying to allow the use of the factory harnesses with as little modification as possible.
Also, you can use small wire and switch in the tent since the relays carry the combined load.
You guys double-check me on this.
The diodes would not be needed, because in the middle position of the switch the bottom relay will still energize the circuit but even it feeds back in to the override relay or top relay the NO pin will be open or not energized so it dosent matter. With your design there should be a diode on the NC pin of the bottom relay of the bottom relay to match the top design or you create the same loop if one or more of the trailer switches are on and the override relay was on that also wouldn’t matter. Good design you just don’t need the diodes.
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