Three wire 12v receptacle from SMB??

[Ben10281]

I have a 12v receptacle on the driver's side wall behind the front seat and next to the rear captains chair in my SMB. I would like to replace it with a dedicated USB outlet instead of the generic round receptacle that is there. I pulled the existing one that SMB installed out of the wall today, and it has 3 wires attached to it. A white one (10AWG) that is connected to the outside of the barrel, assuming that is ground, then a red(10AWG) attached the the end of the barrel and another smaller red(18-20 AWG??) wire also attached to the end of the barrel. Any idea why there are 3 wires? There is no illumination ring or anything.

[arctictraveller]

Possibly to power a light or something? No matter what, it should be fused when attached to a higher amp circuit.

[marret]

Maybe to a switch? One would think it is fused...

[Scalf77]

This is could be the wire that goes up to the ceiling lights, I would have expected to tap into the 10awg up higher but this they might have perceived this as easier. If you look at the manual you will see a couple of circuits that are tapped into the 30 amp driver side circuit. (Ceiling Lights, CB Radio) theses are both 18 awg. The ceiling light fuse is under the front panel where the wires go up to the penthouse roof. The transition fuse 10 Awg to 18 Awg in my mind should be closer to that transition.



Of course it could be one off customization, but it should still have a fuse for the tapped smaller gauge wire (unless the 10 awg circuit fuse is small enough to cover the 18awg wire. It is probably 30-amp, which is to high for the 18 awg wire)

[Ben10281]

Thanks all. I will tug on the wires some more to see if there is a fuse in the wall somewhere.

Here is a picture.

[N147JK]

2 different potential power sources, house battery or chassis battery?

[posplayr]

Originally Posted by Ben10281

I have a 12v receptacle on the driver's side wall behind the front seat and next to the rear captains chair in my SMB. I would like to replace it with a dedicated USB outlet instead of the generic round receptacle that is there.

I just put two of these on my motorcycle off of the switched ignition power. They seem to work as advertised (i measured input voltage from 10V-22V and output voltage (5V USB) and current up to 1.5A (it varies wit the attached device; ports are rated to 2.1A). The benefit is they can be flush mounted wherever and have a small LED to see the plugs.

These are both USB-A but I have seen USB-A and C mixed pair as well.

https://www.amazon.com/dp/B08K8QQJTT...roduct_details

https://www.amazon.com/Charger-DAMAV...091CSCH6M&th=1

[Twoxentrix]

This may help some with deciphering how/where wires are routed (I pulled the picture from a thread another member shared a while back, but unknown how much applies to each model year since I’m sure they re-tooled over the years) - still thought it worthwhile:

[BrianW]

For USB outlets I prefer the flexibility of using an USB adapter plugged into a standard 12v round port. Easy to replace if it goes bad, I can move it around the van as needed, and I can use the 12v port for regular 12v needs too. I don’t really see the upside to dedicated USB plugs?

[bisonthecruiser]

I'm with BrianW on this. They make plenty of flush mount 12v plug versions. The charging specs change every week it feels like and your new phone won't charge as fast with the older one, etc....