Does my MC8355 work?

I have a ThinkPad T420 which comes with an MC8355 modem but I can’t work out if it works or not.
Can anyone tell how to find out? Either using Windows 7 or 10…

I guess you can check in device manager

I’m unable to connect anywhere and wondered if the modem was locked or something… I’d like to find some way to talk to the modem, ie issue AT commands if possible, but don’t know how to do it.

Did you see device manager

Device manager sees it but I can’t do anything with it. I guess it is locked to some network, and apparently I can find out by issuing some AT commands, but don’t know how.

Is there any modem port

Windows Device Manager has this unit in three places, network, modem and port. Can I issue Hayes AT commands if I select modem?

You can use tera term to opem modem port for AT command

I’ve installed tera term and don’t get any response to anything I key in. What next?

Not working for AT commands?

No. How can I tell whether the modem is dead or not?

Others can use AT command

Can you try in linux