Hello @master1900,

A battery change should not cause a lost of communication to the controller.

How did you proceed to the battery change?
Did you check if everything is connected right after the change?

Regards.

Hi !

Thank you for replay.

I have clarified the problem.
The problem consists of the following steps:
1. Replaced disks with larger ones (from 4TB to 8TB)
2. The array went to lock mode.
3. Take out the controller, disconnect the battery and the battery.

Hi !
How to solve this problem correctly?
I am very grateful in advance....

Hello master1900,

I am sorry you faced with this issue.

After replacement of physical disks controller is in lockdown mode, if I understood correctly. Could you please share Dell Five-Digit Part Number of new physical disks, I would like to check their compatibility with MD3800f, regarding this matrix:

https://dell.to/3rRdAdO

How to find Dell Part Number:

https://dell.to/3rRdAKQ

Regarding lockdown mode, troubleshooting steps you can also check here:

https://dell.to/31I4DIP

Please ask me, if you have any questions

Maria Januszka

#IWork4Dell

Dell | Social Outreach Services - Enterprise

Hello, I have the same problem with md3800i. One controller works the other one is not recognized. The following characters are alternately displayed on the back of the device: 5E dF

I am attaching photos below:

Hello Paul587,

This thread may help : http://dell.to/3VU2S20

Was anything done on the unit before this started?

Have you reviewed the Recovery Guru and what does it say?

if you have a serial cable it will tell you what the fault is.

DF is i think a diagnostic fault.