Problem with drivers fmb920

Telematics Question
1

Hello,

I am experiencing an issue while trying to configure my Teltonika FMB920 device.

The main problem seems to be related to the drivers. I downloaded the Teltonika COM Port Driver from your official website and installed it, but the installation does not appear to complete properly.

In Device Manager, the device shows up with a yellow warning icon, and I am unable to get it recognized correctly. The Teltonika Configurator also cannot detect the device and keeps searching indefinitely.

Here is what I have already tried:

Installed the driver multiple times
Disabled driver signature enforcement
Reconnected the device and updated drivers manually

Despite these steps, the issue persists and the device is still not recognized.

For context, I am running Windows 11 inside a virtual machine (UTM on macOS). I am not sure if this could be affecting driver installation or USB communication.

Could you please advise on how to properly install the drivers or suggest a solution for this issue?

Thank you in advance for your support.

2

Hi,

Good Day,

In a virtual environment, the physical USB port belongs to macOS first. If the host doesn’t “hand over” the device to the VM, Windows will see a ghost device or a generic error.

  • USB Passthrough: Ensure the Teltonika device is explicitly captured by UTM. In the UTM toolbar, look for the USB icon and ensure the Teltonika COM port or “Communications Device” is checked.

  • USB 2.0 vs 3.0: Try switching the USB controller settings in the UTM VM configuration.

Force Manual Update via “.inf”

Since the device shows a yellow exclamation mark, Windows knows something is there but can’t link it.

  1. Right-click the yellow icon in Device Manager.
  2. Select Update Driver > Browse my computer for drivers.
  3. Choose Let me pick from a list of available drivers on my computer.
  4. Click Have Disk and browse to the folder where the Teltonika drivers were extracted (look for the .inf file).
  5. Force-select the “Teltonika COM Port” even if Windows warns it isn’t compatible.

Hardware & Cable Verification

It sounds simple, but the FMB920 is sensitive to power.

  • Data Cable: Ensure they are using a high-quality Micro-USB data cable. Many cables bundled with consumer electronics are “charging only” and lack the data lines necessary for the Configurator to see the device.
  • External Power: Ensure the FMB920 is connected to a 12V/24V power supply. While some units can be powered via USB for configuration, the FMB series is much more stable when it has external power during the initial driver handshake.

Thanks

Ashutosh S.