19-01-2024 09:34 PM
Hi guys,
I've my S21 Ultra having Mobile Network issues since almost two weeks.
I saw it is something that happen to other users. But, how to solve?
I tried changing Sim card, etc.. The issue is clearly the smartphone.
Any idea?
Thank you.
Solved! Go to Solution.
16-01-2025 11:57 PM
Guys, this solved for me (for now):
Open the smartphone from the back, unscrew the sheet which cover the antenna (the "cable" on the right), unplug the antenna, clean the connectors, re-plug the antenna, close carefully everything.
I'm currently posting with 5G of the S21 Ultra.
17-05-2025 09:17 PM
FIXED - $8 Flex cable replacement from Amazon (pictures and links below).
Context - 5 months of unpredictable loss of signal (unable to use data, make calls ect - unrelated to signal strength) on a Samsung Galaxy s21 Ultra on Google Fi. Trouble shooting through Google FI completely useless. Changing carriers did not fix the issue.
CAUSE/FIX - a broken connector for a the flex cable that apparently connects the main motherboard to the USB C port. I replaced the part at home with a Y0 size screwdriver and a hair dryer (to warm the back plate). Only took ~15 minutes following a basic teardown video.
This was the replacement part from Amazon:
This was the most helpful YouTube video:
https://www.youtube.com/watch?v=cU3QXPoFOUI
For reference he touches the broken end of the flex cable at exactly 5:14 in the video
Here is a picture of the broken cable from my phone. If you look closely at the port at the top (SUB side) you can see the connector is broken.
Here is a photo from inside the phone.
Note that the circled side has a broken piece of the male connector that I had to remove with a small set of tweezers. The arrow points to a broken portion of the female connector. I was worried I would need to replace the entire USB C board but the connection has been flawless so far despite the fact the board (female) side looks broken. I will update this post if the connection issues come back.
Hope this helps someone - ewaste is such an issue I'd hate to see a phone thrown away for such an easy fix.
19-01-2024 09:46 PM
19-01-2024 11:17 PM
20-01-2024 03:39 PM
21-01-2024 08:15 PM
So what is the solution?
I saw different users complaining about this problem since about two weeks, but not a word by samsung itself.
A reset of the network doesnt work. Going in Offline Mode solves for just few seconds.
Reboot doesnt solve.
The smartphone is pretty new. It is ridiculous to have this problem with a high-grade smartphone.
30-01-2024 08:17 PM
Ehi Samsung, still you there? Anyone with same issue with different phone?
04-03-2024 02:51 PM - last edited 04-03-2024 02:53 PM
I might have the same issue with my Samsung Galaxy S21 5G. For the last couple of weeks my mobile network has been acting weird by not always sending/receiving mms and not updating some app feeds sometimes.
09-03-2024 12:11 PM
Ehi, have you solved?
09-03-2024 08:00 PM
Not yet 🫤
17-03-2024 09:40 PM
Ehi Samsung, any update?