Ignition Live in the bed?

Hi folks,
I have bought a wireless rear camera system, which has a separate screen and receives the camera signal via wireless transmission. The camera just needs a 12V and ground, the manual says to use the reverse light 12V, but I would like to have it on always as I am going to be installing a topper soon, so the rear view mirror will be redundant, I wish someone would make a 3rd party system to copy a couple of other brands that switch on the factory reverse camera when flicking the rear view camera, I guess it will be coming soon.

Is there a ignition live in the rear of the bed, or tap into the trailer wiring perhaps that has a wire that goes live once engine is on?

 

Try the hot wire on the 7 pin connector. Just tap it and see if it works.

This picture isn’t specific to the tundra but gives an idea.

 

I've used the trailer wiring for a tailgate light bar.

 

Yep, this seems to be the best, and perhaps only option. Any idea what is the fuse rating on this 12V?

 

I’m pretty sure it’s a 40A fuse for the trailer charge circuit / 12V ign power (pin 4 of the diagram posted by @timsp8)

 

Many thanks