Xiaomi MI 4i is the new smartphone from Xiaomi. This smartphone comes with MIUI 6 which is updated version and latest vision after MIUI 5. Which using any smartphone from MI with MIUI 5 it was possible to have 3G Only mode but after update to MIUI 6 it is not possible to change this from network option but don't worry i have got one new option from which we can set 3G only mode or and many other option for network selection.
You might have known to some secret codes which are used to see or change settings in any android device. And like this there is one code *#*#4636#*#* which is used in Xiaomi MI 4i to change network mode. below there are few snapshots from Xiaomi MI 4i which will help you to understand this better.
step by step to set 3G aas only network mode-
1) Open settings and in setings open About phone and then touch four times on "Internal Memory" or Open dialpad and dial *#*#4636#*#* .

You might have known to some secret codes which are used to see or change settings in any android device. And like this there is one code *#*#4636#*#* which is used in Xiaomi MI 4i to change network mode. below there are few snapshots from Xiaomi MI 4i which will help you to understand this better.
step by step to set 3G aas only network mode-
1) Open settings and in setings open About phone and then touch four times on "Internal Memory" or Open dialpad and dial *#*#4636#*#* .

4) press back key 3 times till you get back to home menu.
Congratulations this steps will change network setting in your Xiaomi MI 4i and any other device which is running on MIUI 6.
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