Thank for your kind response, guys.
I thought the built-in boot loader was damaged before and then I realize that maybe it's not, because when i boot KT up to main via mfgtool, and then select the restart item in the Menu-Setting-Menu-restart, it does seemed to restart and then stuck in the normal startup screen(the tree). Maybe that means the built-in boot loader still working?
If I select D) D) Q) in diags(boot to diags via mfgtool), the screen froze at diags main menu, not stuck in the normal startup screen. I think this is the reason we think about the built-in boot loader was screwed up, it seemed the restart process failed to start.
So these are some details I didn't describe, would it help?
