Someone please wave their magic wand and make it possible for an aftermarket DVD player to use the 4Runner's built-in software controls.
No because I just went through this for my car and ended up finding something that works. Is it an LE, SE or SR5? And which type of factory audio system? With or without the JBL stuff and with or without the navigation? BTW, what are you trying to have an after-market DVD player tie into your car's computer anyway?
It's the Limited V8 4x4, with the nav system. Nav system has an interface for controlling and watching the factory DVD. Toyota & the aftermarket guys are telling me that you can't integrate an aftermarket system with the head unit. (I did not want the factory DVD system becuz I want headrest screens, not a flip-down.) No clever ideas from the 4Runner forums either. My hope is to avoid the kludge of a separate box for the DVD controls.
Oh okay... I thought you were wanting to do something else. I've not heard of something like that either. Although if you want it bad enough you can always get a electrical engineer to make a bridge for you. I was pretty close to having someone make something custom for my car because no one made it. Then all of a sudden Alpine announced exactly what I wanted at the CES show.