Had same problem. Replacing the sim card at the Sprint store didn't help. What helps is taking the sim out then back in. The under settings - system updates - update prl. Sometimes I have to do this a couple times. We have two LG G3s both over a year old and both show no sim whenever the phone shuts down due to low battery. Can't wait for my two year updates.
I’ve tried taking the sim card out and cleaning it. I’ve shut it off and turned it back on many times. Last week, the wifi turned on (magically) for 2 whole minutes (!), so I know that it’s possible for it to work. I hadn’t even done anything; it just turned on (and then off). I now have a system update waiting to be installed but it won’t let me do it unless I’m on wifi. My 2 years is up in January and it can’t come soon enough!
This was posted on help site of CNET:
1.Start by turning your router off and then on again.
2.Take your LG G3 battery out and then put it back in again and restart the phone.
3.Go to Settings > Wi-Fi and long press on your router and then tell it to Forget network and set the connection up fresh.
4.Make sure that the Battery saver isn't responsible by turning it off. If it is then you can head in and change the settings so it doesn't turn off Wi-Fi.
5.Try turning off Bluetooth if you have it on, sometimes it can interfere with Wi-Fi.
6.Tap the menu button at the top right of the Wi-Fi screen and access Advanced Wi-Fi. Try changing the settings in here.
7.If you have the option to connect to the 5GHz band instead of 2.4GHz, try it.
8.Install Wifi Analyzer and check how busy your channels are. Try switching to a less busy channel if that seems to be the problem.
9.Check with your ISP or router manufacturer to ensure that you have the latest firmware for your router.
Sure you have probably tried all. One person solved by setting router for static gateway for LG G3, another person got it working by removing the battery for minute and then rebooting. Appears to be a common problem.
Yes I have that problem right now. It pisses me off. The wifi wont turn on the button turns itself off. Did you get it fixed? how? xxxxxxxxxx
Sorry to hear you are experiencing issues with your devices, this appears to be a software issue, you can perform a master reset (A master reset will result in the loss of all data stored on the device including 3rd party applications. It is highly recommended that you complete a backup of the device information) For instructions click here. You can also take it to a Sprint repair store to get assistance from one of our technicians. For a complete list of Sprint Phone Repair Centers and to set up an appointment, go to sprint.com/storelocator
Please be sure to go to the Repair Center for assistance, they will be happy to help you!
Sprint Social Care.
Thanks, Ina, but I've gone to the Sprint store twice and they were rude and not helpful and couldn't help me with this issue. Is a master reset the same as a factory reset? If so, I did that but it did not fix the problem. And now I have an even bigger problem because the phone gets stuck on the boot-up screen and will only turn on once in awhile.
We are here for you and I'm going to do everything I can to make sure you get this resolved. Please reply to the private message I sent you.
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