Engg./test & Service Mode codes

[Tripura]

Pls..... help me by giving the codes to fetch TEST MODE & SERVICE MODE in my zenfone 6. I have an issue in NETWORK BAND changing. it does not change automatically, locked at one 4G band. So I get very slow internet speed at that network band. Also I want to test my camera & sensors works properly or not.

[victor010]

Hi there. kindly follow the below steps:
1 . To enter SMMI test
Go to Calculator=>type " .12345+= "
you will be entered to SMMI_TEST_V4.1.35
Select Receiver1_Test=>Press Start to check 
2 . You can't change band by yourself so if you have any internet connectivity issue you can switch SIM and see if the issue remains
3 . Update firmware version if you have not already.
4 . Check with your network provider if the issue persists there.
5 . Last option would be to visit the service center to have a
check. Locate here: https://www.asus.com/in/support/Service-Center/India