Error with HP Smart Array P420i

[Chebur1]

Hello. 
I have ProLiant DL360p Gen8 with HP Smart Array P420i. About a month ago , it issues the following errors in the iLO:

"Drive Array Cache Module Battery Failure (Bus Unknown, Slot 0)
____________________
POST Error: 1805-Slot X Drive Array - Cache Module Super-Cap is not installed; IMPORTANT: Unsupported Configuration: Cache Module cache functionality is limited. Action: Install the Super-Cap to remove these limitations."

In the device statuses themselves, everything is OK and there are no errors, and there are also no errors with batteries.

The error appears at the start of the server and after about a month of its uninterrupted operation.

The version of the smart controller is 8.32, there is still 8.32(C), but the official website says that who has version 8.32 installed, it makes no sense to upgrade to 8.32(C).

I searched the Internet for information on forums, and no one had a similar problem.
All with such errors, the smart controller is already in the "Degraded" status or there is an error on the battery. I have no errors in the status, everything is in the "OK" status.

Please tell me what the problem may be and what is affected by these errors?
Can there be problems with the HDD cache due to such errors?
Thx!
Moderator edit: Removed the confidential info. 

[BunnyPon · Accepted solution]

If this is like the old one I had, it may be that your supercap has passed on. It probably needs a visual inspection just in case it has swollen up, leaked its magic jelly, stuff like that.

A dead battery effectively disables write caching, so you will notice a performance hit if what you are doing is write heavy (e.g. windows OS drive!!) 

[Chebur1]

Thx for help. My supercap was really degraded. 
I will buy new.

[gipsea]

Hi.

I'm facing similar problem, dl360p gen8, p420i. I replaced the battery as I thought to be the reason of low card performance.

With the new battery I have the same problem. 

I have a home lab and I'm not a professional IT crew. What is teh supercap? Where is it and how do I check it?

Any help, is a bonus

cheers

[BunnyPon]

If it is the same as mine, the supercap thing will look a bit. bloated. As if it ate one too many cream cakes.

You might think of it as the battery, it does the same job.

If you look at this photo of a slightly dead one, the LEFT one is normal, the right one is a goner.

This photo is from one that came with a Microserver Gen 8. I seem to remember the 1U servers had a completely different shaped thing that fit in a holder. 

Close up of a super cap

[gipsea]

@BunnyPon 

thanks for the pic. I thought to be some part on the cart itself. I have new battery now. battery looks good.

I think I should look for problems somewhere else

Cheers