i was using tenda battery powered router since last 1 year it was working well but now i got a problem with it
on the ip page it show status connected and also in windows connection settings it shows internet access but it does not gives connectivity to the internet .......... but sometimes after resetting it again and again it starts working ........i tried every thing i upgraded the firmware and etc but still got the problem please help me

Same thing happens to me, but not after one year. It went like this from the first time. Here is my e-mail to Tenda support:
"Hello,

I have purchased a Tenda 3G150B wireless 3G router. I am using it together with a Huawei E3131 3G dongle.

Problem description:
Right after the router is booting and connecting to the modem, everything works fine (Internet connection works).
If I use it's web interface to manually disconnect it (or automatically, by using "reconnect on demand" function) and than reconnect it back, it says that it is connected but the internet connection doesn't work anymore. I also noticed (in 3G statistics) that there is some data transmitted but no data is received.
This never happens after a fresh reboot, but only during router up-time.

Can you please help me out with this issue?"

I am waiting for their answers. I will keep you updated.

In the meantime, does anyone have any clue about this issue??

I have also emailed tenda support with the same issue.

At first when using the Huawei E220 puck with the 3g150b I got no error message and had to reboot the router for the connection to work. When I tried with a Huawei E169 stick i get a "sim card not detected" error after about 18-24 hours.

I tried a different usb power source (thinking it was a lack of juice) but still the same problem (two Type A to Mini B with both USB ports capable of 2.1A on the new adapter). I tried a different simcard (Telia and 3) but still the same problem.

When checking the logs I see several LCP down messages and it doesn't seem to be able to detect the modem. I will post screenshots later as I need to go and reset the bloody thing again

Another thing I have noticed is that pin codes need to be deactivated before using the simcard with the router/modem. Entering the correct pin into the admin interface will not work.

edit: according to this user on youtube https://www.youtube.com/watch?v=ManO9Zk4uGo he has the same issue but not very often.

(Last edited by Fenix on 27 Nov 2014, 11:52)