Replacing Nav Display
Failing that, I'm not above hacking in a completely new custom system into the top display... While this wouldn't give CarPlay, it could do some other neat things like bluetooth. - there are some pretty amazing things that can be done with a Raspberry Pi these days. I've already got a CANBUS module for one. Anyone got any down and dirty details on the inner workings of the Nav system (connections, protocols, display standard, location of the actual box... )
I was in the same boat last year with outdated radio and obsolete NAV and I didn't want 2 screens either.
Swapping a -Non-Nav Info Display- for the Nav is the easiest and fastest and cheapest and most reliable workaround IMHO.
Here is the writeup I did on it. https://www.clublexus.com/forums/rx-...o-non-nav.html
Others have had sucess with a Tesla style unit but until someone makes a retro-fit bezel with physical AC & Info buttons(not android touch) I'll keep what I have cuz I wasn't crazy about the idea of a proprietary all-in-one unit that could fail and leave me nothing.
PS- The AC & Info data runs thru the multiplex BEAN network and can probaby be hacked by an Arduino(with CAN) but would be some work to identify messages and still have problem of no bezel with buttons to work with it.
Pricey but a mostly Plug and Play solution with a company that has great support. Not much can be done with the actual OEM Nav display, as you found only the radio itself can be swapped.
The idea is the same with the VLine product while the raspberry can give me the carplay... I can always switch back the screen to its original to change AC, sound....
There are a couples of things need to sort out
1. Display: the same idea with Vline where they use their customize GVMF cable to connect the vline and the screen while still allows the HU takes over the screen if needed. Still do not know how do they do that

2. Touch screen: how to use the raspberry to control
These two things need to be solved otherwise there is no point to think about how to get the raspberry communicate with the audio system, buttons on the wheel...
Vline is an easy plug and play option but is pricey for a 10 year old car.







