Help. Changed master cyl & 12v. VSC, ABS, Brake lights, beeping.

So I got the dreaded ABS lights and we could still hear the pump clicking, so we decided to change out the brake master cylinder. We also swapped out the 12v to complete the flush, as previous battery seemed to be dying. After we flushed the vehicle, the lights stopped and the car worked for about a week. After a week, all of the same symptoms came back, but after a couple of hours sitting the car was back to normal. Then while driving, same thing, lights and beeping and brakes felt off. But after 10 minute, it went away. Drove all day yesterday fine, but this morning when I start the car, the brake felt stiff and the abs lights and beeping aren't going away. I didn't hear the pump click, so I'm assuming it either isn't getting power or failed? All seemed so well after we swapped the master cylinder, so now I'm trying to diagnose if it's the actual pump assembly and if that needs to be swapped or if I'm missing something. Thanks.

 

My friend had the proper techstreAm software and the computer for it. He did it just like they do in the shop. We followed the instructions, jacked each tire, he had me pump 8 times then hold to get all the air out. Did for each tire. Then let the software do its thing. That said, I only had 3 codes initially. When I went back recently I had 2 new codes that weren't there previously. C1202 and c1365 are the new ones. C1252, c1253 and c1256 were the original codes. All of the symptoms pointed to the cylinder as we could still hear pump. I'm wondering if the pump kicked the bucket now. They said normally the pump is good, and it was ir seemed like. But now the brakes feel completely gone, i dont hear the pump and the car is almost impossible to stop if not going very slow.