Z5C - Mobile Data Connection Within Wi-Fi Range

[cako]

I am just sitting on my office desk, 2 meters from the router all day. But the phone keeps connecting to mobile data and just takes 5 kb of data for 20 -30 times a day. I fiddled with automatic background data settings, with no success.

What do you think? Anybody else experiencing this?

[MarlonUk1]

you can try to turn off mobile data...  settings>data usage>click mobile data switch

or if you click the option button( 3 dots) you can restrict background data

[Phy]

could you boot on safe mode and test the WiFi connection, make sure to disable the data.

How to boot on safe mode
http://talk.sonymobile.com/t5/FAQ/How-to-boot-your-phone-into-safe-mode/m-p/348008#U348008

How to boot on safe mode on Lolipop
1. press and hold the power key
2. once you get the pop up menu 
3. press and hold "power off" 
4. Boot on safe mode should become available