EM9190 Modules not detected by any OS on different computers either on USB nor PCIe

Happy new year!

Before going any further into the description, here I am describing the problems related to the bare module, not the Evaluation board, I do only have the module itself.

I have an EM9191 module, brand-new, I just took it out of the package and installed it directly into an M2 socket B, however, the module did not show up.
Then I used a USB adapter, which, of course, failed again.

I understand the module is by default in PCIe mode, please can someone confirm?

Another key point, does the module requires a specific type of M2 socket B? I just read that the module requires a PCIe 3.0 compatible interface to work ‘properly’ , but I have no clue what kind of M2 interface I got, I just know that it’s a key B, can this be the root cause of the problem?

Many thanks!!

Does this help?


Yeah sort of, I already checked that post, but it speaks about the dev kit, and I don’t have it, I just have the module, I don’t have any switches or interfaces beyond the m2 itself…

have you checked the PCIE_DIS pin?

I read about this PIN, but I don’t have access to any other interface than M2, and unless that PIN is somewhere available in the module itself (not in the development board) I don’t have any means to change it, or maybe I am missing something?


did you check PTS? You can measure the pin status on pin 20

Ehm, do you mean to somehow connect to the contact number 20 of the M2 socket that contains about 60 pins? That sounds quite hard to achieve without special equipment, at least I have no idea how to do that without actually soldering something to the board… is that what you meant?


No, i don’t have m2 socket
I used the usb port in dev Kit

Can you check the schematic and measure the pin 20 of the module?

Hmmm, that would be definitely challenging, that would involve soldering a wire to the female m2 keyB connector of a board (any)… Tricky maneuver

What about the debug pads behind the module, is there a way to get into the module to set the mode, or at least to check if it is alive?

I would like to exhaust the means before calling it for warranty…

do you have multimeter to check if those pads are connected to pin20 of the module?

Yes I do, but I think that should be already known by Sierra Wireless engineers or at least present in some documents, maybe field service documents?

I just checked the following document:

I believe you can direct measure the pin 20 of the M.2 socket

BTW, do you measure the current consumption when power on?

Hmmm… that’s tough to do really, it is an embedded system that has many other things running at the same time, so … I don’t have any means to directly measure the current.

Maybe, I should get myself a Development Board … or, can you point me to an USB adapter that has been tested and it is compatible with the module please? , I think though, this adapter must have a way to indicate (thru pin 20) that it is on USB Mode, is that possible?




so far i only use the USB of the development kit…
I don’t try other USB adaptor

But you can have a look here: