I am installing a Directed DVD player in a 2011 Yukon. I need to find a wire that has 12 volts only when the ignition key is in the ACC position. Any one have any ideas?

1st off, welcome to the forum, Larry! My 1st thought would be to look for a wiring diagram for your particular vehicle, so, that way, you'll be able to find what you're looking for. But, someone else on here may have the info you're looking for. Hope this helps!

It would be much easier to spend the extra $10 to get the wiring harness. Plug n Play baby!

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I agree with Mike, way less trouble to install the aftermarket deck and your wiring harness us undamaged and ready to install the stock radio if you decide to sell the truck.
METRA® 71-2105 - Chevy Silverado 2008-2011 Wiring Harness, For OEM Radio

even with the harness you have to find the 12v keyed. what you want is the RAP circuit. i use one of the fuse taps so you dont have to cut factory wires. you just have to test something in the panel to be on only with the key

Correct me if I'm wrong. But the newer systems these days have a 12v constant to the radio correct? And its the data bus that actually turns the radio on? And Larry is needing a 12v switched power for the aftermarket stereo correct?

thats correct after 2000 or so depending on the model no 12v switched to the radio, so the adapters just come with a red wire you have to connect to the RAP circuit somewhere