How to change 3G to 4G on android phones with in Qualcomm Chipset Processor:
- For open Engineering mode in qualcomm chipset processor phone download and install “Shortcut Master Lite app”.
- Open it and click on Menu.
- Search for “Service Menu” Or “Engineering Mode” and select it.
- Now you can change the preferred network.
- OR Dial *#2263# then Select Menu and Click Back again then Select Menu.
- Now go to Key Input and Enter “0000”, Select UE Setting from Popup.
- Select the desired band by going : Configure Protocol>NAS>Network Control>Band Selection>LTE Band>
Switch between 2G / 3G / 4G LTE on android mobile phones with Mediatek Chipset Processor
If your device is used mediatek chipset processor then follow below steps to use 4g sim in 3g android mobile phones.
- Download and install Mtk Engineering Mode app from play store.
- Open it and click on “Mtk Settings”.
- Under Telephony scroll down , to “Network selecting/Preferred Network” Option.
- Now select the desired network from the list.