Best under dash wire to tap for ignition-on power
 

I got an Audiovox backup sensor kit for Xmas (the kind where the sensors are mounted in a step that slips in the towing receiver). It plugs into the 7-wire plug in the back. So, no problem there. The wireless receiver is located in the cab and can get its power from either an accessory plug (cig lighter style) or can be hard-wired. I'd like to hard wire it. So, I need to tap into a power line that gets hot when the ignition is on. Can someone point out which wire in my 04.5 Laramie would do that?

I'd use the cig lighter wire.

Isn't that one hot all the time? I think that's the lower one on the 04.5. The upper one is on with ignition, but not sure if I can get to the wires going to it. Worth checking, though. Also, maybe I can get to one of my wires going to the Prodigy. It's only hot with ignition on.

I'll tell ya after work, I know that's the one I used for my gauges...

The cigarette lighter is only on with ignition. I tapped it for a number of accessories.