BBWC not charge in DL320s

[egen]

I have a server DL320s. After the next firmware update (7.22) P400 controller is no longer charged battery BBWC. 
Once the battery is discharged, the controller gives an error 1793, off the accelerator and proposes to replace the cache on a new one. 
When installing the controller in the other server battery charges normally and the controller begins to operate normally. I tried to install the previous firmware, but it did not solve the problem. 

I also tried replacing the cache and battery with a new, but it did not help. 

I went to the service center where the server was purchased, but they could not help me.