You have to recalibrate the screen. Now if the ribbon connected to the screen is somehow damaged you're sol.
Frankly I do not know why Pioneer does not include this with the operations manual.
It seems that my screen calibration changes with temperature and humidity. So naturally the screen gets out of wack in the summer.
Anyhow, this is what you do.
1. open the face of the D1 all the way, as if you were to eject the dvd nav disc (but don't do it).
2. hold the reset button (just above the joystick, you need a pen to do it) and the nav disc eject at the same time.
3. let go of the reset button
4. let go of the dvd eject button. the screen will say "press reset"
5. push the joystick up twice.
6. push the joystick down twice.
7. then press the joystick. wait a few seconds and you should be in the service menu. You should be able to navigate the service menu using the joystick.
8. okay this is the tricky part. Go to the screen trace screen (I don't remember the exact name), it should be the first menu item. A screen will come up with the perimeter of the screen outlined. Trace the screen with a stylus. This somehow lets the D1 to know the available area that is "active"
9. press back, which I think is the "P.ADJ" button on the lower right.
10. go to the second menu item which is the touch screen calibration. Just use your stylus and touch the "+" sign on the screen. It's much like calibrating a windows mobile touchscreen. You will have about a dozen "+" to touch to get the screen calibrated.
11. You can mess with the other menus to see if your screen is "really" calibrated.
Okay that's it. I think the D1 resets itself so you will lose your radio stations, etc. And the nav will reset so Los Angeles will show up on the nav screen for the first minute or so. So don't get alarmed.
Now here's the thing. After initially going through this thing, I could not get it to calibrate correctly in step 10. I kept pressing the "+" but could not get it to acknowledge that I've touch the screen. I suspect you have the same problem as I. So in step 8, this is what I did. When you trace the perimeter of the screen, do not go all the way to the right side perimeter. Lay off it by about 1/4". This tricks the unit in thinking that the usable screen is smaller. Then go through the rest of the steps as usual. In step 10 you may have to be off the "+" by about 1/8" of an inch to the right. You will know what I mean when you start doing it and messing with it.
Believe me, I know that it is frustrating that the touch screen buttons are off about ~1/4" to 1/2". And half the time the on screen zoom buttons and audio adjustment buttons do not work. However, if you follow this procedure, I'm willing to bet that it will work. The screen may be off just a wee bit, but at least you can access all the touchscreen functions. Give it a try.