Hello thanks for choosing Dell. Could you perform a cold boot (plug out power cables for about 3 mins) during maintenance including chassis?

Hi there, this has been done and same result.

Hi @diaz.cloud,

Can you please check and confirm if you have also received an event message informing "The internal communication between the Chassis Management Controller (CMC) and the control panel is restored".

I do not happen to see that log in the chassis log or the hardware log. Below photo is the only thing I see in regards to this issue.

Hello, have you tried the recommended actions in the screenshot you attached?

Yes as mentioned previously, this unit has been power cycled quite a few times and left without power for some time as well.

Hi @diaz.cloud,

Can you please refer to the below document and try to reset the CMC.

https://dell.to/3x2rlrr

After performing the CMC reset there is no change to the critical error regarding the LCD screen, any ideas on what to do next?

As your other colleague has already mentioned this, I do not see the restored message. Additionally the LCD is completely functional so not quite sure what is going on here.

Hello https://dell.to/3x8lzV2,

It looks like this is an error that can occur but resolves shortly after that.

Do you see any entry near that error that says communication restored,

Message ID = HWC8503

Message = The internal communication between the Chassis Management Controller (CMC) and the control panel is restored.

Knowledge Base Article Number: 000146758

CMC - Event HWC8504 "Chassis Management Controller cannot communicate with the control panel"

https://dell.to/40DAdBb

Solution:

Hardware replacement is not needed. While there was a communication error, communication was successfully restored in a timely manner.  The issue occurs across the I2C bus which is a low level (100kHz to 400kHz) serial synchronous communication bus.  It is not uncommon to observe a communication error from time to time across this bus.