I just installed my radar detector and after quite a bit of investigation I did find a wire in the center console. It turns on when you open the door, not when you turn the key, but close enough. If you look at the Start/Stop button's illumination, it makes that behavior. Been using it for a week know and I am happy with it. There is a ton of circuitry in that center console. I marked up the image in this thread to identify the wire. But, I would still verify this wire's behavior beforehand.

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