Why Does My LG G3 Display 4G LTE But Actually Has No/Slow Data Connection?

[Traci Carter]

I recently purchased a LG G3 on Swappa, per seller it was a refurb sent to her directly from T-Mobile. I transferred my T-Mobile SIM card from my Samsung Galaxy S3.

Previously, with the Samsung, at home, the device would show 4G in the taskbar, and I would actually get 4G speeds, between 15-25 mbps on speed tests. At work, the Samsung device would show 2G or Edge and my data was not so good, less than 2 mbps if any. This is common for most people in my office.

Now that I have the LG G3, it ALWAYS shows 4G LTE in the taskbar, but actual speeds at home are 2-5 mbps and work is no connection at all.

After Googling for help, I've tried toggling Airplane mode, restarting the phone a million times, removing and inserting the SIM card, manually entering APN settings, resetting default APN settings, turning on Data Roaming, and many others. The only think I haven't done is update to the latest software, because I despise Lollipop and I'm waiting for Marshmellow to become available.

I know this may be an issue with T-Mobile service, but the fact that the data speed is showing incorrectly in the taskbar makes me think it may be a device problem instead. Any thoughts on what may be wrong?

 

[Rukbat]

It could also be a bad antenna connection, causing a weak signal. (Check the mobile data line in the second page of the battery stats - it should show solid green - if not, the signal is weak.) It really has to go into a shop for diagnosis, though - or she can send it back for another refurb, if you can get her to work with you. (Sometimes you have to return a few refurbs - because the "refurbisher" they're using just checks the phone cosmetically, changes a screen or back cover, and sends it out.)

 

[Traci Carter]

After some more extensive Googling, it looks like I've just got a product/service that don't match up. LG G3 apparently doesn't recieve on LTE Band 12, and I am in one of the areas that T-Mobile switched their LTE service over to Band 12. So, no LTE for me. I switched my Network Mode to GSM/WCDMA auto, and now I'm getting my 10-15 mbps 4G speeds again. Still sucks at work, but that was anticipated, and at least it's showing 2G connection now so I know to expect it to suck. Guess I should have looked more into the specs before I bought, but I'm happy enough with the 4G speeds. Thanks for your help.