I have a 2018 Lexus LS500, a we could NOT get the video to switch correctly. When you went to the Hamilton side, it would work, but holding the menu button, and switching back to the Lexus screen...produced a blank screen. After MANY attempts to fix....here's the issue. My car did NOT have the CarPlay update installed. It turns out that the car needed service bulletin L-SB-0028-19 installed. This updates the car and allows reliable video switching. You can pay a dealer to do it, or DIY (for free) by reading this: https://www.toyotanation.com/threads/apple-carplay-update-files-18-toyota-camry-sienna-18-19-lexus-models.1652876/page-44?nested_view=1#post-15186410 The files you need are on the first post. There are also files listed for other Toyota models..... I hope this helps.
