How To Fix Wi-Fi or Mobile Data Connection Issues on Samsung Galaxy S4 [Part 1]

Problem #4: Samsung Galaxy S4 randomly changing networks (1X, 3G, and 4G)

Hello. My US Cellular Galaxy S4 began having 4G problems about 2 weeks ago. It began randomly switching between 1X, 3G, and 4G. When on 4G the upload arrow will light up, but the download arrow will not. If I turn off the LTE network settings it will function on 3G just fine, if a little slow. I took it to a US Cellular store and replaced the SIM card and re-activated the phone. I replaced both the red and white external antennae,  and performed a factory reset. None of these things have corrected the problem. I also have the latest software updates. Is there anything else it could be before I take it to a repair shop for potentially costly repairs, or trade it in? Thanks for your time. — Joshua

Solution: Hi Joshua. We think you have already done what we are supposed to tell users with the same problems like you. Please proceed to have the phone replaced or repaired instead. We don’t think the issue has something to do with the firmware here. However, you can try to boot up the phone in safe mode to see if that will make any difference.