@chaos239 it should not pull anything with the battery disconnected, until you turn it on. Once turned on it should pull the proper amps. I would replace the charging board and the flex from the charging board to the main board. While you are there, also change the battery. Should this not fix the issue, the error will be on the motherboard. Double check all of your flex cables and connectors first.
Since iFixit does not have specific guides for this phone, use the ones [https://www.nadiemellamagallina.com/en/manuales/smartphones-1/samsung-4/samsung-galaxy-a13-sm-a137-1378/|from here] They are all written in Spanish so you may have use a browser that does th translating for you.
While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.
Repair is War on Entropy!