Fitting a USB Port

[Ginge@72]

Hi
This maybe a silly question but for peace of mind sake here goes.
Having a 2006 swift we have no USB ports, we just install a double usb in the 12v port in the van.
We would to like install a double port by the stereo so we can run WiFi router and charge it and the option to charge other devices without taking up space else where.
As it will be near the stereo I thought I can take the power of the stereo wiring, so would I need to tap into the yellow cable for constant 12v or the switched Red cable and then obviously black for negative.

Here’s my USB PORT

 

[JTQ]

If into the sustained supply it will be something else draining the battery in storage, and I can presently see user no benefit at all from using that sustained feed.

 

[audiorob]

Don't know the answer to the question - but if it is any help you could replace a standard 13 pin socket with similar that also has 2 usb outlets. Can't see a beige so far but certainly white or black or silver or nickel one of which may suit the van decor. Also if you search within this website for 'How to fit a usb socket in your van' by LIzzie Pope the article may help you with some of the details. It was puiblished in 2017 but I am sure is still relevant.