the firmware is or was the current v5.3.1! When i press 2 times the power button the kindle will be detected but as a device not as flash drive :/
i found the MFGTOOL, it connects with the pw but no update or "fastboot" process start.
this is what i actually see:
I found this and i could restart! http://factory-reset.com/wiki/Kindle_Paperwhite
But now when it reboot i came back into the "usb device mode" with ENABLE_DIAGS and the pw appears great as flash drive and i can browse into the files.
NOW, how can i remove the "ENABLE_DIAGS" file? It disappeard...