huawei 3G modem disconnects instantly

Asked by Theo on 2012-06-01

I use a Huawei 3G modem (E352) to connect to the internet. My modem was detected and I made a new connection, my ISP Airtel was in the list. That was fine so far. But when I connect, it always disconnects after 10-15 seconds. And the modem disappears from network manager. If I reconnect the modem it appears again in network manager but on connection it disconnects and disappears. Strange!! Though lsusb always shows the modem no matter whether it is connected or disconnected or disappeared from network manager. The modem works fine under Windows, no problem persists there. What's wrong with it under Ubuntu 12.04 LTS ?

Here's an output of lsusb:

"Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 003: ID 1c4f:0002 SiGma Micro Keyboard TRACER Gamma Ivory
Bus 001 Device 006: ID 046d:c05a Logitech, Inc. Optical Mouse M90
Bus 001 Device 005: ID 12d1:1506 Huawei Technologies Co., Ltd. E398 LTE/UMTS/GSM Modem/Networkcard
Bus 002 Device 004: ID 04e8:689e Samsung Electronics Co., Ltd GT-S5670 [Galaxy Fit]"

Question information

Language:
English Edit question
Status:
Answered
For:
Ubuntu gnome-nettool Edit question
Assignee:
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Last query:
2012-06-01
Last reply:
2012-11-17

Windows sees the device as a USB storage and installs the driver on the storage (Because it is primitive), the modem itself is nothing but a serial modem which has had Linux support for a LONG time, Linux doesn't need, nor can it use the Windows driver.

Once Windows installs the driver it 'flips' it to be a modem, so in Linux the device just needs flipping to be a modem. This is done by the package usb-modeswitch.

http://ubuntuforums.org/showthread.php?p=10766923

codemaniac (arijit.dutta) said : #2

Sakis3g script automagically setups your USB or Bluetooth™ modem, and may even detect operator settings. You should try it when anything else fails! .

http://www.sakis3g.org/#downloading

Theo (itheo92) said : #3

Well, I researched a lot about the topic and came to know all these (i.e. the composite device, CD-ROM emulation, the flipping, usb-mode-switch etc etc). But still my problem is unresolved.

This is really a strange and odd looking problem. My modem is actually detected by network manager, that implies the mode switching works. But it disconnects in a few seconds after dialing up and the modem vanishes from network manager. I don't have a clue for this.

Again, if you look carefully at the -lsusb output, you'll see that it shows the modem as "Bus 001 Device 005: ID 12d1:1506 Huawei Technologies Co., Ltd. E398 LTE/UMTS/GSM Modem/Networkcard". But really this is a Huawei E352 3G (neither E398 nor LTE) modem. I think (also saw this in some other forums) the E398 and the E352 has a shared PID or VID, that's why Ubuntu detects the E352 UMTS device falsely as an E398 LTE device. This might be the cause of the problem. Is it?

I tried a Huawei E1731, that works fine and stays connected for hours without dropping. lsusb shows "Bus 001 Device 007: ID 12d1:1436 Huawei Technologies Co., Ltd. " for this device.

I'm really pretty confused of all these. The problem becomes more and more challenging.

Theo (itheo92) said : #4

I tried sakis3G. But unfortunately it doesn't works in Ubuntu 12.04 LTS.

codemaniac (arijit.dutta) said : #5

But it works fine and out of box on 11.10 .Have to check it out on 12.04 .

Marius B. Kotsbak (mariusko) said : #6

The output indicate that you are using a "E398 LTE" modem. Are you really having a E352?

Олег (barminov-oe) said : #7

I have same problem and sovle it by downloading a sakis3G by instruction (near download button) and it works.
Use Ubuntu 12.04.1 amd64

The proposed solution, going to <http://www.sakis3g.org/#downloading>, is not longer available.

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