I'd love to find a wire to tap for the courtesy lights. I've been wanting to add some additional lighting for that, as the two little LEDs in the mirrors are not the best.
I've come up with three possibilities:
1 - Tapping the footwell lights. These wires will handle the draw of a T10/194 bulb, which average 0.27 amp. I've got the OEM LED ones installed, so there's some spare amperage available there. They are easy to get at, right up under each footwell in the cab.
2 - Tapping the Cargo light. This one may or may not require a relay to avoid having the can-bus system shut it off. The problem with using a relay is that the cargo light fades out and may cause chattering of the relay. The wire is under the drivers side door sill. On my 2014 it's supposed to be white with a tan stripe.
3 - Tapping the dome light. Pretty much the same issues as the cargo light. Not sure where/what color the wire is. Also, my truck has the factory LED dome, so the can-bus is not expecting much amperage draw.
For anyone curious, here are the amperage draws @ 14v that I measured on the Recon Big Rig Ice lights I have here. These are per side.
Running Light: 0.07 amp
Turn Signal: 0.38 amp
Courtesy Light: 0.15 amp
-K