I have a Z1 with Z3 upgrade. First the unit will work when it want's to, but, not reliable. Every once in a while it starts to travel about 1000 mph eastward. All icons disappear and no buttons work. If I push the compass and the map button fast, it will go back to the map screen for a while. Then after a reset it may or may not get going again. Now the touch screen won't work. I can't even get past the OK screen. When it did work, could be today, it will navigate, but, goes on another fast eastward direction until I push on the red triangle. Weird. It works for days and then acts like this for days more.

Sounds like a touch screen going bad, lose connection internally, or you have a screen protector that is causing the unit to "think" you are touching the screen...

Sounds like a touch screen going bad, lose connection internally, or you have a screen protector that is causing the unit to "think" you are touching the screen...

Now nothing happens. It gets to the OK then I can't go any farther. Reset no help. It's dead.

I think it's the touch screen.

Today it works, but, I'm afraid to do anything but look at the map. So it's an intermittent thing. As soon as we get home it's going to the doctor.