Mobile network fail after 4G (LTE) activation

[Garrik1]

After activation of 4G connection with mobile network drops out. The only way to restore the connection with mobile network is to return to 3G/2G network and reboot the device. Is it device issue or mobile operator problem? What are the ways to resolve it?

[Alexander1]

Hi and welcome to the community! Since you're new please be sure that you have checked out our Discussion guidelines.

Try to turn off the phone and remove the SIM card for a while. Put it back in and try to see if it gets better. You may also want to check that you have the network mode set to LTE/WCDMA/GSM and if you open network operator, and set the search mode to auto. 

If the behavior still persists, I would suggest that you try with another SIM card in your phone. 

[Garrik1]

First method doesn't help. LTE network is visible but when I try to connect to it connection fails. Now I'm going to try another SIM card. Should it be SIM card from another operator or just another SIM card from the same operator?

[dm841]

what network are you on ?, Try to dail *#*#7378423#*#* go to service tests >antenna switching, change network mode to FDD_LTE rx diversity settings to both rx antennas enabled(default) make sure it says set rx diversity sucessfully 

[EnglandFlick]

Perhaps it's the networks LTE bandwidth support, some cellsites or regions doesn't support full LTE connection so when you choose 4g/lte/wcdma/gsm the phone would automatically prefer the 4g connection for faster download speed in which Qualcomm is very know for, that's the reason why when you shift to 3g/wcdma/gsm your phone is working perfectly fine. Since the site might only supports for 3g or H/H+. You better stick to 3g. Ask your locol network operator if the area youvare in is supporting 4g network. Lte is still new and many areas are still not enabled to have this tech. Hope that helps you

[EnglandFlick]

Plus some sim cards are LTE enabled or not, better ask you local operator about any iterations of lte sims. Prepaids are known to have this issue or your lte connection isn't enabled by your local network.

[Garrik1]

The problem is solved. It is mobile operator problem, not phones. On other operator sim card all is working pretty well.

[Alexander1]

Great! I'm glad to hear that you solved your problem. 

[Jonatan-lee]

Hi there i think i have a similar issue to this post and i will be very grateful if you can help me with it. i have a xperia Z3 compact and apparently its hard for the phone to switch between LTE and other networks and viceversa because as you know in Mexico the LTE its only on certain areas so when i go from LTE to another section where i know the LTE its not supported the signal die and i have to put the phone on plane mode to refresh the signal on H or H+ and the signal is so inconstant sometimes i have 1 bar, sometimes 3 but only on certain places (counted with the fingers of my hand) i have all the signal. Did you know what can cause this issue? i try another network company, another sim card but the results are the same the signal its so inconstant  then how do i know if is a switch problems ? well because sometimes rarely got all the signal after switch from one network to another, i don't discard that probably its a hardware issue with the anthena or something like that.