Lexus RX 2004-09 :: Navigation System Giving Message - Insert Correct Disk

I was playing around with the navigation system of my 06 RX400H because I read about the motion override online; however I was being stupid and chose the wrong option under the "load" menu, so the navigation system kept telling me "insert correct disk. ". Hoping that I could find a simple "reset" option there, I was playing with the diagnostic mode quite a bit. One setting allow you to select the navigation unit start up logo between Toyota, Lexus, and None. There is another interesting option called "car setting" don't know what it does.

Seemed like it let you toggle between a numerous of settings, I remember one being 9001X4WD or something. I didn't know what the setting does and accidentally changed the vehicle setting for my navigation unit. After confirming the edit, I realized that the mapping for all the buttons on my panel completed changed! First of all the map button (which wasn't working at the time because I had the wrong load option) became the "Audio" button that is similar to the audio button on my other car, 06 IS350, it showed me all my audio presets and I could choose using the touch the screen (normally this feature is disabled for RX400H).

I realized I might have screwed up the setting and wanted to change back to the original vehicle setting. I couldn't find much information online, so I figure I probably hit that set button by mistake 2 or 3 times, so I reverted the car code back to what it was 3 selections ago, and bam! My panel buttons are messed up even further! Now I don't even have access to the "info" button any more! I can still get access to the first level diagnostic mode using the "display setting" (display key is mapped to the info button now) then left upper corner + left lower corner method, however I can't change the vehicle code in this mode.

I took the car to a local dealer, and the service tech was like "what the heck did you do" and he said he don't know how to fix this except to replace the whole navigation ECU which would cost thousands of bucks. I asked him it would be as simple as getting access to the onboard ECU memory and rewrite it and he said the data format is Toyota proprietary and the dealer doesn't know how to fix it.

Of course I wasn't satisfied with the answer I got, I took the car home. Following some good information on forums and navigation ECU replace instructions on AllData, I was able to remove the navigation ECU from the car, then took it apart, disconnected the power daughter board, pushed the black reset button(?), and then put everything back together. I have seem people saying this method working and not working, but for me it did work. When I restarted the vehicle, the "loading data do not turn off" screen came on, and after the system booted, GPS navigation is working as usual now. On e interesting observation, before the GPS unit has established a connection with the satellites (took about 2-3 minutes to do so), the default location for the vehicle in the system is somewhere in Washington D.C.

Now I have undone my "load version" mistake. However, without the "info" button being mapped to the dashboard, I don't even have access to the menu where you can change the "car code", so even if I know the correct code now, I wouldn't be able to enter it. also it seems that I was able to reset the ECU when I took it apart, I am suspecting that the setting for "car code" isn't store in the ECU but it is stored somewhere instead.