Erricson F3075G Unlocking Notes

15 Mar 2010

Sony Erricson F3705G Unlock

How to network-unlock the device using ubuntu:

Well I couldn't use the lenovo broadband manager to unlock in windows 7, it would just crash the program without unlocking.

You can do a similar procedure under windows XP using a serial terminal such as hyperterm or realterm to execute the commands below if the erricson wireless manager does not work to properly unlock the card, you will just need to find the correct serial control port.

It was locked to ATT:

Called ATT and got unlock code after 1 week via email.

Install a different sim card from another network

Boot into ubuntu 9.10

install gtkterm

sudo apt-get install gtkterm

run gtkterm open port /dev/ttyACM1 at 9600 baud 8n1

Now type:


If the card is network locked (Eg only works with ATT and you have a different card in the laptop) then you should get a response:


If you get +CPIN: READY then it is already unlocked what is important is PH-NET is there as this means the card is locked to a particular network.

To unlock type:

AT+CPIN="The Network unlock code given to you"



If this is the correct code the card will respond with:


Remember you only have a few tries to unlock the device

To double check run:


The card should respond with:


You are ready to go and your Erricson F3705G is unlocked to any network.