USB Flush mount wiring help


Sep 17, 2010
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Hey guys,

I'm starting a little project here and would love if someone with more wiring knowledge than myself could look this over and tell me if everything looks correct. The goal is to replace the stock power socket beneath the stereo with a fixed USB panel mount with two USB charging ports. (I know this is kind of a frivolous project, just doing it for the hell of it)

Previously, I changed the wiring of the stock power socket to be fed by the constant 12V power instead of the accessory power so the socket is powered even when the car is off.

Here are the two products I intend to use for this project:
USB Panel mount
12V to 5V Converter

And here is a diagram I drew of how I planned to wire these into my car:

I am going to cut off the male USB plugs and remove the insulation to reveal the 4 wires inside each cable each containing a positive and negative wire to power the ports, and a positive and negative data wire which I will connect together to cause a short (which I understand should allow for faster charging since these ports will not be used for data)

I'd greatly appreciate if someone could look this over for any potential issues, I think I researched it properly and it seems like it should work. My biggest questions/concerns are:

1.) Do I have the right idea as far as shorting the data wires together?

2.) Can I wire the both the positive and negative wire from each port to the same 12V to 5V converter output wire, or do I need two of the converters and need to keep for instance the positive from USB port #1 separate from the positive from USB port #2?

I'm fairly confident about everything else, but question #2 above in bold is my primary concern and uncertainty.

Any input would be greatly appreciated!


Well-Known Member
Dec 25, 2016
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id honestly get one of these or something similar and just cut the cig lighter socket end off exposing just 2 wires the power and ground. then you can flush mount it or do whatever .

already has built in converter and is known to work on a vehicle 12 volt system.

much cheaper/ easier then splicing and soldering small gauge wiring and risking it shorting.


Well-Known Member
Feb 8, 2013
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I would see if they make one with a built in converter; since its less splices and less points of error or problems.

I would not leave it on constant. I would wire it to something ACC. It could eventually kill your battery if your charging something with a big draw for a long time

Splicing them together depends on what output the converter has and what draw you're charging. I believe new phones are 2.0 a faster charging, laptops and such maybe more.

Looks cool, good luck.