Problems with my Latitude 5520

My Dell Latitude 5520 shows the following code 8AC6D992 and it does not work if I disconnect the battery. 
The battery check shows that the condition is excellent. In addition to that, I had to re-enter the service tag
in the BIOS Setup several times, and the fan also speeds up. 
I have already performed the corresponding BIOS updates. 

What can I do? 
Regards