2006 w/ nav MFD touchscreen stopped responding

I have run into my first scary issue with my beloved '06 Prius purchased new in March 2006 . The car hasn't seen the dealers service department in over a year thanks to the courage that this site has given me to do my own maintenance and I'm just hoping to keep it that way for a little while longer.

The display is still fine, but the touchscreen won't respond. It happened suddenly. I was at a red light so I decided to start to program the nav for an upcoming business trip but it did not respond. I couldn't hit the accept button on the nav disclaimer. The next time I came to a stop I tried a few other screens and at one point it seemed like the screen needed to be calibrated because I touched one button but a different one above it on the screen registered. I took a deep breath and hoped that somehow it would start working again the next time I used the car. I have not gotten it to respond since.

Is there any way possible that this could be a 12V battery issue? (grasping at straws). I can do most of what I need to do with the steering wheel controls, so my main need for the screen is the GPS. I figure that I can get a portable GPS for cheaper than getting the problem diagnosed.

Most of the MFD's that I have seen on ebay are for cars without the nav and some have been listed as supporting '06 models produced through 10/05. Will I have to take the dash apart to find the exact replacement part number or will I have to purchase the service manuals to get that info.

 

The car has been powered off and on many times (issue started 4 days ago), but not specifically the MFD. Thinking about disconnecting the 12V battery to see if that resets anything.

The screen is clean. It only had erratic behavior for a brief moment and then no response at all after that.

 

The touchscreen does not work on any screen. It worked flawlessly until the day it stopped working. Unfortunately I have a business trip this week, so I did not have an opportunity to attempt to disconnect the battery or test it.

 

So after all this time, I finally got brave and ordered an MFD salvaged from a 2008 from ebay. I got it for $300 play $15 shipping. I took the dashboard apart and plugged in the replacement and it worked like a charm.

As I discovered from other threads, the bluetooth module is in the MFD so I lost my phonebook and the bluetooth pairing when I switched. Now that makes me wonder if salvaged MFDs could possibly contain someones phonebook.

I am elated because I can finally use my navigation again after all this time. My wife is happy because she can finally play with the radio stations from the passenger side again.

 

Actually my car is a 2006 purchased in March of 06. I didn't have any of the symptoms of the 2005 MFD issues. I'm not sure if I happened to get a lemon or if something struck the screen and damaged it without leaving any physical evidence. I'm usually the only driver of my car, but is has been to car washes and driven by parking lot attendants.