VR7000 wont start even though it is fully charged

I have the powerbot vacuum for over a year now and the vacuum cleaner suddenly stopped working. I am still able to charge it by placing it on the dock. However, after the initial startup 3 beeps, it doesnt produce the usual melody and the 3 indicators went off for awhile, then the battery indicator starts blinking while the other 2 is not lighted up.

I suspect there may be a problem with the main PCB. Is there anyone facing the same issue and managed to fix it? Any help will be greatly appreciated!