I searched for this but just about everyone points to a mod for being able to view the rearview camera with a new switch.

I have a headunit (Kenwood DNX 7140) that has a wire to the reverse lamp harness in order to bring up the camera image. It also includes an option to view the reverse camera by selecting a button.

I would therefore like to find a constant (when the vehicle is on) power source in the back of the truck that I can use for the camera. Anyone know of anything? The power cable is pretty short - can I just extend it with a quick purchase at Radio Shack?

License plate lights? rear outlet?

ah yes, forgot to mention rear outlet was my first guess, was wondering if that would work. thanks

yeah i have my amp turn on signal wired to that.

Wouldn't you still need to run both wires to switch? Why not find a constant in dash to run to switch and then have one wire run yo camera.

Sorry, not exactly sure what you mean. I'm not very good with this stuff (which is why I'm trying to do it myself, to learn something - hopefully I don't start a fire in the process!) I'm tapping into a constant source in the back because it comes a short power cable (though I might still have to extend it). I'm running the video into the head unit, which will then give me a choice for when to display the image (if I go into reverse, because it has a reverse sensor, or by selecting the "rear cam" input)

Having it run off of accessory power without a switch is not a problem. Just be sure to use the fuse that is inline for the power. If the wires aren't long enough, adding wire is not a problem either. Just be sure to use the same gauge or larger (smaller number), and again, don't cut the fuse out of the equation by adding the wire.

If you run power off of the power receptacle, just be sure to remember if you do the power on all the time mod, your camera will be on all the time.
I connected mine to the accessory power at the JBL amp, which is located in the right cargo area. Of course, you may not have JBL, so just pick a source.
The ground doesn't need to be grounded at the same place you get power from either. Pick a nice convenient bolt under a panel and burnish the paint away, so you have a good contact, or simply splice in to another ground (there are plenty of junction connectors that have good grounds). Just be sure to do a good quality splice. DO NOT USE WIRE NUTS!!!! Use splices made for the vehicle environment, and either solder, or splice them (or both).

Your camera only pulls milliamps, so that really isn't a concern when looking for where to connect.

Good luck

Thanks for your help!

Tested rear power for with my charger before getting deep into the project - not working. Through some searching it looks like it is the PWR OUTLET 15A fuse, but I can't tell if that is used for both the front and rear power sources.

Is there one fuse for front and rear power? Or is it something else if the front still works but rear does not?

Just found a nice diagram from Kmvreter, looks like it is one fuse for both. Guess I will be finding another power source - not really trying to inspect the length of that connection, unless there are other ideas.