Chosen Solution
So i bought 2 broken screen galaxy s8 from different people. Then i replaced the screens but after i replaced the screens the sim card signal became very poor. At home i can call people. But at some places i get no signals even though my other phones show full signal at the same place. Also when i am at home or somewhere else i receive messages really late and i also sometimes don’t receive some calls. When i call someone when there are full signals the call works but then if i use data it is too slow. And sometimes even if the calls work the data doesn’t work. I know its weird that i have the same problem on both phones. I tried replacing the charging port and the antenna cables but still i wasn’t able to fix it. Please tell me how can i fix it
Hi, Don’t know the phone but looking at the ifixit Samsung Galaxy S8 Motherboard Replacement guide, at Step.21 it mentions the two antenna cables which I assume that you replaced and at Step.22 it mentions the antenna ribbon cable. Did you check to see if the ribbon cable was connected properly or even if it is there (see Step.31-32 Samsung Galaxy S8 I/O Daughterboard Replacement guide)?
