Data keeps cutting out for ~15 minutes at a time

[littlebum2002]

The oddest thing keeps happening to me. Every now and then, my data just shuts off. It is gone for about ~15 minutes to an hour, then comes back on.

I recently bought a used Galaxy S4, and when I first bought it this happened about every day, then it stopped for awhile, now it just happened again (about 4-5 days since it last happened) so I figured I would try to find out what's going on.

But what's happening isn't making any sense. I have full bars, I have t-mobile on the top, I can make calls, and my data is turned on. It's just not working. Turining data off and on doesn't help, neither does resetting the phone. The only thing that helps is waiting. When my data is on, I almost always have fast 4g data, I don't have any issues with connectivity.

I took a screenshot of my Settings screen (with private data removed) for reference.

I don't know if this helps, but at first the only time this would happen is when I would leave a Wi-Fi connection. I figured the phone just was taking too long to "realize" i wasn't on wi-fi anymore and mobile data needed to turn back on. However, I turned off wi-fi for the last week or so and have been using mobile data exclusively. That's when it started happening less, it's happened about every 3 days since I turned off my wi-fi and about every 1 day before then.

 

[Rukbat]

Check the signal strength when you lose the connection. If there's no signal, head for the nearest T-Mobile store. It could be your radio or your baseband firmware, but it could also be their local tower. If it's the phone, flashing a new stock ROM might fix it. Ask them which of their stores does device support.

 

[littlebum2002]

I've checked the signal as soon as I discovered the 4G was gone, and never noticed a missing signal. I've tried my wife's phone while my data is MIA, and hers works fine, so I don't think it's the tower.

I was thinking of re-flashing, but figured I'd have to do it myself. I didn't realize the T-Mobile store could do it. I'll have to go ask them.

 

[Rukbat]

If they do it, they're responsible for the phone. (IOW, the warranty stays in effect and, if something goes wrong, they owe you another phone.) If you do it, and there's any difference between the ROM you flashed and the one that came with the phone (and they can tell), you've voided the warranty, even if the phone still works.

When I said to check the signal, though, I didn't mean to look at the bars on the notification bat, I meant with an app like Signal Check Light. Just leave it running in the background and when you lose the signal, switch to it and see if the signal level is the same as it is when you have signal. If T-Mobile has techs where you bring the phone, that information, either way (it has the same signal or it loses the signal) will help them to diagnose the problem.