STOP.
You do not need to call Pioneer yet. I've had exactly the same problem. I've asked many questions and for help in the forum but I've had to solve it on my own. (Thanks to some kind friends in the forum who tried to help)
This is a mysterious lock up when booted in the test mode and while you think your unit is dead, the blank screen you see is actually caused by a wrong back camera setting changed automatically for some strange reason.
Although you can correct this problem, probably the next thing you'll suffer from will be the inability to enter language settings and/or change the voice language (if you need to)
Here's how you get out of this.
BLANK SCREEN: Put a sharp object (a pen, needle) in the reset button under the eject button to reset the system. Then you will be able to boot in once correctly since the system will bypass all settings including the back camera. Immediately go into settings/system settings/back camera. You'll notice that the setting is suprisingly set neither on nor to off but the voltage parameters are asked as if it is on. Just select OFF. And turn off your car and back on. You should be in with no problems.
LANGUAGE FATAL ERROR: If you get a fatal error message and a reboot in entering the language settings, doing a "factory setting recall" on settings/navi settings will enable you to go into language settings with no problem
CAN'T CHANGE VOICE LANGUAGE: If your system freezes when trying to change the voice, boot into testmode go to Myflasdisk/user/userdata/setup and delete all 5 files there.
When you reboot, the system will ask you your language preferences as if you installed the machine for the first time. Choose the ones you like and the system will start up as normal. You' should not have the freeze problem again. You may see in igo that it shows another region or country when done this move. Just go into destination/adresses and change the country and city to your preference and you have a brand spanking new and full working system.
CONSTANT REBOOTING: Other users have found workarounds for this already. It requires you to boot into testmode delete Myflasdisk/user/userdata/igo/save directory. Then if this is not sufficient you may need to put the universal igo license file into Myflasdisk/APL2/igo/content/license without deleting the Pioneer one.
The universal license file can be found by searching the forum.
I really worked my a.. of to get this worked out but it would be the biggest hassle and unnecessary cost to have my unit sent to Pioneer.
Hope this works for you all. Good luck.
For moderators: You may want to sticky this so that I am saved from writing this over and over and AVIC owners are ssaved from sending their units back to Pioneer to have reflashed. 