I'm trying to install a gun rack/lock in the trunk of my 04 TL. I need to splice into a constant source of power and i'm having difficulty finding an appropriate place. Any suggestions? I need something that isn't going to shut off when the trunk is closed.

There is a huge bundle of wires on the left trunk arm but I can't figure out what they all are.

 

I can't find a diagram in the service manual, but check the trunk light wires. One of them should be hot all the time. I think the trunk light works off of the trunk latch so when it's closed the light goes off and when you open the trunk the light goes on so that must make the ground connection, meaning the other wire is always hot. Just hook up your tester to one wire at a time and close the trunk. You can run the wires through the pass through so you can check it when the trunk is closed.

 

the center cigerate lighter in the console has constant power, you can run a wire from there, also the power motors for the windows and seats are constant, so you can tap into the interior fuse box and run a wire to the trunk.

 

My 05 TL has switched power in the center console, my radar detector is spliced into it and it is off when the key is off.

At least I think so... 99% sure that it is switched. Put your phone charger in there verify it before you take everything apart and with this assumption.