So this is an interesting one. Some of you might have a RinseKit Pro. If not it's a portable shower 3.5 gallon with built in pump and motor. Super good for camping, surfing, hiking etc. They come with a wall plug and also a cig lighter style power plug. What's interesting is when you plug the thing in at the back outlet with the truck off The head unit and clock come on! It's not a big deal but I'd really like to be able to keep it plugged in so when the truck is on it's getting charged so the battery in the rinse kit stays topped up. Last thing I want to do is either drain the truck battery or drain the Rinse kit battery because the headunit is powered up. Again the truck is off and key is in my pocket.

I'm guessing this outlet works both ways and that what's actually happening is the battery in the rinse kit is powering the ACC in the truck, i.e. Radio and clock.

Not something I've dealt with and I'd rather not mess with the wiring on this truck because it's mint and want to keep it that if possible. But it would better if it only worked when the truck was on or even better running so if there is a mod you guys can think of I'd be willing to do it.

do you have a 3 prong outlet in the back? that should only work when the car is on and would solve your problem. does that rear cigarette plug give power even when the car is off if you plug something else into it?

You are right, the battery in the shower is powering the acc circuits in the car. Not a good design or idea. The shower plug in should have a one way diode so current flows from the car to the shower, not the other way.

Edit: I’m surprised the 10 amp fuse for the 12 volt outlet hasn’t blown. Certainly, the current flowing back from the shower battery to power the acc circuit may be above 10 amps.

The shower should be designed to run off it’s own battery, not the car’s, and use the 12 v outlet to only charge the shower battery.

I looked this device up on google and it appears to have its own AGM battery
Why not charge directly to the battery under the hood with an adapter w/12v plug with the correct fusing. It looks like all it needs is an occasional charge.
Plus if it blows a fuse it will be outside the truck.

So I've switched to using the outlet plug in the back next to the cigarette lighter plug. Problem is I often forget to hit the switch for the plug to power on. I kinda wish it was just on when the truck was on and off when key off and out. I guess I could rewire the switch but again don't really want to.