Tapping power from USB-C harness?

Indecent Dad

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Hoping someone with experience in this sort of thing can chime in….
I need a usb-c cable on the back side of this switch panel to charge a device out of sight (charge only, no data).
I am trying to avoid a fuse tap since the only fuse panel I can find is in the engine bay (side question…is there a fuse panel under steering column??)

I assume the USB-C harness will already be converted to 5V DC for the pre-existing charge ports on the right??
Is tapping pre-existing wires here a bad idea?

IMG_7646.jpeg
 
So two solutions........

There is an interior fuse panel under the glove box (remove the trim panel).

Purchase a splitter from Amazon and new OEM port, remove the existing port, split it behind the trim panel, install new port into original hole.
 
So two solutions........

There is an interior fuse panel under the glove box (remove the trim panel).

Purchase a splitter from Amazon and new OEM port, remove the existing port, split it behind the trim panel, install new port into original hole.
Perfect! Interior fuse panel it is - looks close enough to where it won’t be a pain running a cable. Thank you!
 
Perfect! Interior fuse panel it is - looks close enough to where it won’t be a pain running a cable. Thank you!
Personally I'd run a wire from the Dvr's side under hood fuse box into the area you are trying to power. All you need is an Ice pick and a fuse tap. If you look on my build page for how I did it. There is an easily assessable firewall pass through that already has a rubber grommet installed and all you'd have to do is poke a hole in it, no other tools required. There are several unused (empty) "always hot" and "hot with key on" that accept a fuse tap........ and your done.
 
Personally I'd run a wire from the Dvr's side under hood fuse box into the area you are trying to power. All you need is an Ice pick and a fuse tap. If you look on my build page for how I did it. There is an easily assessable firewall pass through that already has a rubber grommet installed and all you'd have to do is poke a hole in it, no other tools required. There are several unused (empty) "always hot" and "hot with key on" that accept a fuse tap........ and your done.
That’s the plan then! Especially after seeing the tiny fuse box on passenger side…don’t think a tap will work.
Will refer to your build
 
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To answer the questions about USB-C port output: USB-C allows an output of 5-20V, negotiated between the source (oem usb port) and sink (dashcam) using the chips built into USB ports as well as inside of the cables, something like this inside:
1732121266749.png


By default, per USB-C 'standards', a fully implemented female USB-C port has to provide 0V until a higher voltage is requested (but there are definitely 5V-only USB-C ports like cheap power banks etc). Seeing as the vehicle's electrical system is 12V, the oem USB-C port is probably 12V on the input end. It's out is certainly not only 5V because it allows something like >30W output (at least on the other Toyotas.. I haven't checked this on LC). If it were 5V-only it would have to be capped at a lower power output.
 
^oops I didn't mean 'dashcam' specifically, that was an example.

But yeah the fusebox is covered by a plastic panel with little clearance so tapping it is almost a non-starter unless you decide to not use the plastic panel. Here's the wiring diagram from Toyota for the USB ports. I would just buy a standalone USB converter and tap it in parallel to any of the USB ports. Probably the one called 'USB NO.1'

1732122192431.png


Look around for these connectors (E36 and K35 are the same type) and pay attention to the wire colors and use a 2-wire t-tap:
1732122459284.png


1732122410068.png
 
Got impatient waiting on fuse taps to arrive, so I went ahead and pulled the dash apart and tapped into the USB harness wire. I am not 100% sure it is the right wire….but it tested at 12v with ignition on and that’s what I needed so it works for me.

IMG_7650.jpeg
 
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