I've got a Kenwood DDX 9903s and I'd like to use the factory USB port to connect my phone for Android Auto.

Has anyone traced the USB cable in the console to where ever it goes to see if it is just a standard USB cable?

If not, I plan on tracing it out and will update everyone here.

I actually did some searching and found a cable that should work for this, if you still need it. The factory cable plugs into the back of the radio and unfortunately it isn't a standard connection.

This, however should work. Plug one end into the factory USB connection behind the radio and plug the other end (obviously) into whatever USB connection you might have on the back of your aftermarket deck.
https://aerpro.com/aphousb1

Yeah, I haven't had much luck. I thought about splicing a USB cable and doing something custom but there is a lot of room for error there. The product you've linked to looks good but I can't find a dealer in the US.

definitely don't wanna splice a USB cable!

I did some more digging.

There is a part number (3911-TFO-003) https://www.ebay.com/i/321468228842?chn=ps&dispItem=1

I've ordered one from amazon (not the same cable, but a generic) that I will attempt to replace the factory plug with. I just need to pick up a male to male usb cable.

I'll update everyone here. The cable arrives sunday.

By the looks of it, that just replaces the USB cable that's already run in the console/dash and you'd still need to find a way to connect the gray plug to your aftermarket head unit, unless you had planned on splicing it and I'm just confused.

Yeah, looking at the photo I thought the grey part was the USB port in the console and the other side would be extended to my headunit but the grey connector is actually just a proprietary connector and I'm an idiot.

Cost of experimentation.

Hopefully that cable wasn't too expensive. I would imagine you could splice a normal Type A connector on the cable in the car for use with your aftermarket deck, and if you ever return to stock you can just install the cable you bought to reconnect it to the factory head unit again.

It was only $6...

I'm back to the drawing board.