No connection in ECM mode

Occasionally we find a modem which does not connect in ECM mode (AT+QCFG="usbnet",1)

Sometimes this happens with the same modem model, firmware revision and SIM being used. One modem will connect and the other one will not.

Are there any known impediments to ECM mode working?

Any other settings to check?

Thanks for contacting us, could you pls tell us the module type and firmware revision you used? thanks

Thank you for your reply.

Personally I had an EM06-E that didn’t work in ECM mode with some SIMs.

That query of mine is old. I gave that EM06-E to someone else.

But I’m a developer for the ROOter project, and there are many Quectel users in the USA for whom ECM mode doesn’t work.

A recent example:

My current Quectels do work in ECM mode. EC25-AU, EM06-E, EM12-G, RM500Q-AE.

Thanks for you query in Quectel forums.
After configuring AT+QCFG="USBNET ", you need to restart the module. After restarting the module, if the network connection is normal, you can use the ECM nic normally. If some of you cannot use the ECM nic to access the Internet, you are advised to check whether the network connection is successful.