NVIDIA DRIVE AGX xavier B not able to boot

Please provide the following info (check/uncheck the boxes after creating this topic):
Software Version
DRIVE OS Linux 5.2.6
DRIVE OS Linux 5.2.6 and DriveWorks 4.0
DRIVE OS Linux 5.2.0
DRIVE OS Linux 5.2.0 and DriveWorks 3.5
[*] NVIDIA DRIVE™ Software 10.0 (Linux)
NVIDIA DRIVE™ Software 9.0 (Linux)
other DRIVE OS version
other

Target Operating System
[*] Linux
QNX
other

Hardware Platform
[*] NVIDIA DRIVE™ AGX Xavier DevKit (E3550)
NVIDIA DRIVE™ AGX Pegasus DevKit (E3550)
other

SDK Manager Version
[*] 1.8.0.10363
other

Host Machine Version
[*] native Ubuntu 18.04
other
Problem description:we have a problem with start xavier B.
The current situation is that after powering on the DRIVE, it is obvious that a fan speed is abnormal, and there is no signal when xavier B is connected to HDMI, and xavier A cannot ping xavier B. When debugging xavier A and B
Through the electrical LED indicators, I found that DS5 and DS15 are off, and DS2 is flashing.
Supplementary instructions
yesterday:,when executing ./sample-drivenet --input-type=camera --camera-index=1 --slave=0, xavier B can also open the routine. Everything else is normal. The shutdown is performed after the poweroff operation is performed on the system, and then the power-off operation is performed. The camera is hot-plugged in the middle, but Xavier A has done the same operation.
From the LED status light mentioned in the document, I did not find the problem of xavier B.Can you help what I doing wrong? Thanks !

Dear @user51700,
Are you able to access XB via minicom?

Please see if Xavier AGX doesn't boot anymore helps with your issue. Thanks.