4G network problems

[oldscififan]

Hello! I am new here. For Christmas, my son got a new phone and I got his old Galaxy S4. I am still learning to use it (less than a month so far) and recently have been having a serious problem. The phone somehow gets into a mode where it cannot find the 4G network. I have zero bars. I know that I am not out of my service area, since it happened at home!

I am thinking that some setting is wrong, or maybe the phone is dying - I don't know. But, I discovered by accident that powering it down and then turning it on fixes the problem. Maybe some app is causing the problem?

Wi-fi is on, data is on, so it is not either of those. Thanks in advance for any help!

 

[B. Diddy]

Welcome to Android Central! Go to Settings>Mobile Networks>Preferred Network Type, and make sure it's set to LTE (or some setting that includes LTE). The menu location might vary with the phone, so let us know if you can't find it.

It's also worth booting into Safe Mode to see if a 3rd party app is the culprit: https://support.t-mobile.com/docs/DOC-11724

 

[blade22222]

When it does this try putting it into airplane mode for five seconds then turn off airplane mode. Should reset the radio.

 

[oldscififan]

Hi! Thanks - so I checked and it was set to Global, which seems the be the default? I had the choice of LTE/CDMA, or LTE/GSM/UMTS - I selected the former.

What kind of indication would there be if a 3rd party app was causing trouble? Sorry if that is a dumb question, and thanks so much for your help! This has been vexing me for over a week!

 

[oldscififan]

Ah, ok - I will try that also!! Thanks!!

 

[B. Diddy]

Hi! Thanks - so I checked and it was set to Global, which seems the be the default? I had the choice of LTE/CDMA, or LTE/GSM/UMTS - I selected the former.

What kind of indication would there be if a 3rd party app was causing trouble? Sorry if that is a dumb question, and thanks so much for your help! This has been vexing me for over a week!

Global should work, but LTE/CDMA is also worth trying.

Use the phone for a while in Safe Mode to see if the 4G drops out. If it never does in Safe Mode, but does it regularly in normal mode, then I'd suspect some 3rd party app (but it can be tough to narrow that down).