Can I force 3G mode while using a USB 3G modem ?

Can I force 3G mode while using a USB 3G modem ?

Atm its working in 2G mode only. I can see the light on the modem and its GREEN.

I went to my ISP’s office and they told me that my modem is very old and no longer supported.

I was just wondering is there a way (under Linux) to force 3G mode ?

:~> lsusb
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 004: ID 2318:2808 Shining Technologies, Inc. [hex] 
Bus 001 Device 003: ID 046d:c52f Logitech, Inc. Unifying Receiver
Bus 001 Device 002: ID 413c:2107 Dell Computer Corp. 
Bus 001 Device 006: ID 12d1:1436 Huawei Technologies Co., Ltd. Broadband stick
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Typically network devices negotiate various session parameters between themselves.
If one side refuses to accept a certain setting, I don’t know that the other can force anything successfully.

The best you can do, perhaps a last gasp try to find something is to do an Internet search on your hardware and see if anyone might have an alternate solution, perhaps emulating or modifying how your hardware is identified.


Hi, your modem should be an Huawei E173 or a local variation thereof; I used it till last year installing Modem Manager Gui to control almost any option available.
It should be possible to set “3G only”, but this does not “force” anything, just expose only the 3G part of the modem: if you have no 3G carrier around you make no connection at all, but if a carrier offers choice you will connect in 3G mode.

My carrier offers 3G and even 4G but since my modem is 3G I don’t expect 4G speeds.

I have installed Modem Manager Gui installed.

Please tell what should I configure in Modem Manager Gui.

Sorry, I last used MM Gui more than one year ago and apparently I didn’t recall correctly.
With MM Gui you can see the current network setup in the “Info” tab: the Network > Mode field should confirm if the provider you are connected to offers UMTS (3G) or GPRS (2G) or whatever.
In the “Scan” tab you can scan for all available carriers at your location, maybe you will find that your carrier is listed twice, possibly with UMTS and GPRS modes available.
Since at the time my provider only offered 3G connectivity, with 2G backup available via roaming, I un-ticked the “Allow roaming if home network is not available” box in the “Mobile Broadband” tab of the Network Manager connection editor.
If you don’t know what I’m talking about please open a terminal, issue


select your broadband connection name and click the “gear” button to open options available (this is on Gnome, maybe it looks a bit different on other desktops).
There should be a way to send other specific codes to the modem via nmcli (please see “man nmcli”) but I never did that to “force” 3G connectivity. IIRC the modem applet on Windows allows something like that, so it should definitely be possible.

If the above is not enough maybe I will be able to find that Huawei modem of mine and do some tinkering, but don’t take that as a promise at the moment :\

Apparently in the olden days the NM connection editor had a dropdown to select the “3G only” mode etc. and that was likely what I remembered (please see for an example). Unfortunately that option was dropped in recent versions of NetworkManager.
But searching the net I also found this reference:
>>>>>>>>>>>>>BE CAREFUL<<<<<<<<<<<<<<<<<<<< use the following at your own risk, I cannot guarantee that it works or that it cannot cause damages.
My E173 is recognised and connected to 3 devices: /dev/ttyUSB0 /dev/ttyUSB1 /dev/ttyUSB2
Opening a terminal and issuing:

su -
<root password>
screen /dev/ttyUSB2

I get some chatter from the modem telling the signal strenght etc.: that /dev/USB2 is the control channel of the modem (it may be another device if you have more stuff connected to the USB bus, so check dmesg to find where your modem is connected).
If I issue:


I get:

^SYSCFG: (2,13,14,16),(0-3),((2000000400380,"GSM900/GSM1800/WCDMA900/WCDMA2100"),(280000,"GSM850/GSM1900"),(3fffffff,"All bands")),(0-2),(0-4)

like would be expected according to the referenced page.
If the other suggestions from the reference also hold true, you may try to send:


to “force” 3G mode only; but BEWARE, I DID NOT CHECK that and cannot guarantee anything (nor does the referenced page).

Hope this helps anyway.