You would use the MaxiFlash and a two day professional diagnostic pass through Toyota's TIS website. This gives you access to the Toyota Techstream application where you can program any of the modules in your ES350. I've programmed new ECMs as well as reflashed/updated current ECMs on several Toyota/Lexus vehicles with no problems. It's a pretty smooth and easy process, and you have 2 days to use as much as you want on as many vehicles as you want.