EM9191 module not recognized on Linux/Win10 host computer

The EM9191 module we have recently acquired is not recognized by Device Manager on Windows 10 or dmesg on Ubuntu 20.04LTS. I am not sure if there is a prior configuration required to operate. When plugged in, the USB module has a brief LED light, but still nothing appears to respond on host computer. We are using a generic USB adapter for the modem from amazon. Despite no visible device, drivers for Win10 have been installed as provided from the installer link. Please let us know if there are any missing steps that we may have overlooked.

See if this helps

The thread linked seems be abandoned and was prior to the device being fully released. Are there any dev boards that I can acquire or a person of contact that help? I do not have any direct communication with Sierra representatives at this moment.

did you check PCIE_DIS signal

Unfortunately, the EM919x is wired in a way which makes it incompatible with any devices designed for e.g. the EM7455 by default (IMHO quite stupid design decision).

If you are capable (or know someone who is) of soldering, it is fairly trivial to modify any USB-m.2 adapter board to pull the PCIe_DIS signal to 1.8V, so USB is activated instead. Create a resistive voltage divider between 3V3 and GND (e.g. 10k to GND and 6.8k to 3V3), and connect it with the PCIe_DIS pin.

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