We live in Portland, Oregon, and get a lot of rain (mainly drizzle). I have noticed the rain sensor system on my new GS350 does not work well when it is drizzling. I find that I frequently have to manually activate the wiper blades to keep the windshield clear, even with the rain sensor sensitivity set to hi. It seems to me that Lexus could have included a coarse rain sensor sensitivity setting in one of the setup menus or perhaps a manual override that enables manual intermittent operation.
Does anyone else have a problem with Lexus rain sensor?