Edit - Jan 2020: I wasn't happy with the Kenwood for numerous reasons so I have replaced it with the outstanding Pioneer AVH-2550NEX. The post contents are still valid in that they describe the wiring needed for the backup cam. I also repaired the images.

Original Post
I just installed a new Kenwood DDX373BT HU and ran wiring for a soon-to-be-installed backup camera. Hope this info may help someone else. Others have posted re the parking and reverse wiring, but even with the pics in those threads, I was still having trouble locating the wires under the driver's side kick panel and the last thing I wanted was electrical problems from screwing up the taps. So I called Crutchfield (who I highly recommend) and the info they gave is below with pics.

First, here's the gear I used:

Crux SWRTY-61S Wiring interface - wire this to the HU wiring plug, then plug into the factory harnesses.

Metra 95-8202 Dash Kit - small trim pieces for each side of the HU.

Hosa Stereo RCA to Mini Adapter - Optional, use if you want to keep the factory Aux plug in the console bin. You'll also need a short (6" will do) female-to-male extension because this adapter is too wide to plug straight into the back of the HU.

T-Spec 20' Video Cable - yep, I overpaid, and others have probably used less than a 20' cable. But I wanted to run this once and once only forever and also wanted no question over whether I would have enough to reach the back regardless of routing, so I bit the bullet and bought this cable. I ended up going across under the steering column, under the door sill trim (there's even a little clip holding another cable there that this one fits right into), up behind the back door to the headliner, then working it underneath the headliner, then zip tying the extra cable in the space behind the driver's side convex mirror pending the camera install.

I had no need to bypass the DVD safety feature so I was looking for the parking brake wire, and needed to tap the reverse wire for the backup cam. Crutchfield's tech rep described the locations as follows.

The plugs described are side-by-side on the left side of the dash fuse box:



Reverse wire - red with yellow stripe, pin #10 on a 16-pin plug. (Note - "16-pin" means there are 16 places for pins; some may be unused & thus empty.) This wire is in pin 10, it's 2nd from the end in this pic but I'm holding it upside down and there are 8 pins across, so if you count from the top end of the plug, the blue wire is pin #9 and the target, the red w/ yellow stripe, is #10.



Parking brake wire - light green, pin #1 on the larger 24-pin plug. Note that the other light green wire has silver on it - don't use that one - you want the plain light green wire in the first pin spot on the end.



You have to work off some of the black protective covering before the wires can be separated enough to get a tap on 'em. I used Scotchloks, love those things.

Also, the 4th Gen 4Runner has two antenna inputs for whatever reason, a large & a small. Most people Just plug in the large one but you can get an adapter if you wish.

One other thing I did was to bring the USB cable down to behind the panel circled in this pic (not my truck, just a pic I found to show the panel). The reason is that this panel easily pops off to provide access if you ever need to plug something different into the USB. For example, a thumb drive for a firmware update or a new phone cable if the current one goes bad or you change phones & have a new style cable. Otherwise you will have to disassemble the dash again to get to it. I tucked my Sirius receiver down there too b/c I can easily change the antenna if the plug comes loose or anything happens to the current one.

It’s pretty easy to get the phone cable out to where you need it.



That's it - happy to answer any questions.