S9 won't mine

[FatAnt]

This one was cleaned on July 10th and has been working OK 'til this afternoon when I noticed it not performing.
I've reset it but it makes no difference, hashing doesn't happen.
Status shows: Hardware Version   Socket      connect failed: Connection refused
Is that supposed to be a clue?

I'm not seeing anything obvious from the log, but I don't know what to look for.
Kernal log is posted at: https://pastebin.com/Mbqy3gvz
I'd be most grateful if someone could point me to a solution.
Thank you.

[BitMaxz]

Can you try to flash it using SD card program recovery you can follow the guide from here S9 series (S9, S9i, S9j, S9 Hydro) Control Board Program Recovery
After that flash it again with this firmware "Antminer-S9-all-201711171757-autofreq-user-Update2UBI-NF.tar.gz" in WebGUI.

After that set up the pool of your choice make sure no extra spaces and make sure you have stable internet then test it again and update here.

[tim-bc]

My guess is power or firmware issue.

What PSU are you using, and what is the supply voltage?

Also that firmware is pretty old, you might want to update to May 2019, or Dec 2018 if you must have SSH.

[Artemis3]

Also that firmware is pretty old, you might want to update to May 2019, or Dec 2018 if you must have SSH.

The reason BitMaxz is recommending 2017 is for a reason: it was one of the last good reliable versions, before asicboost. 2018 is Asicboost enabled, pre-miner locking, thus the only other valid choice. 2019 is garbage.

Telling people to update to 2019 is the same as telling them to lock themselves out of their miners.