The nav system in my mother’s 2007 ES 350 recently (September 2018) stopped responding to touch. But here’s the thing—the touchscreen still works, as I can tap the map screen and it will retarget and move the map. Furthermore, all of the (physical) dash console buttons that relate to the nav system still work, and when I push those to bring up different menus, a very few of them will respond to touch. Most of the screen & its menu buttons won’t respond, however. It continues to work as a live display of the current location & map, but there is no way to actually use it as a nav system because we are unable to enter a destination.
I’ve done a lot of google & YouTube searching about the problem, but haven’t found my set of symptoms. I’ve tried disconnecting the battery, waiting a bit, then reconnecting the battery to reset the system. Sure enough, when starting the car I get the progress bar and “boot-up” screen for the nav system. When it finishes booting, it’s right back to the same behavior: live map, but non-responsive to onscreen button presses.
(My online searches found an extensive guide to removing the unit from the dash, then disassembling it further to get to the touchscreen itself and repairing a broken wire trace. I don’t think that can be our problem, however, since the touchscreen works across its entire surface to reposition the map. It’s just when we switch to Destination entry and other screens that it does not respond. Sure sounds like a software problem to me.)
My mother has taken the car to her local Toyota dealer, and they were absolutely no help. Their only advice is about $2k for a new unit, and forty bucks spent on that diagnosis. She has to drive an hour to get to the nearest Lexus dealer, which she may try soon.
For what it’s worth, she thinks this behavior started after she had regular maintenance (oil change, tire rotation) done at the Toyota dealer. That’s certainly possible, but I don’t see what the connection might be.
Thanks for any advice or pointers. I’m a reasonably handy engineer who can do some troubleshooting & fixes myself, if I know what to try.
