What Do the LEDs on My USB CAN Device Mean?

Updated Jun 21, 2022

Reported In


  • USB-8473
  • USB-8472


  • NI-CAN

Issue Details

I'm using a USB CAN or LIN device and when I plug it into my computer the LED next to the network type (either CAN or LIN) isn't lit up.  What does this mean? Is my USB device broken? Also, what does the color of the USB LED mean?


The USB CAN and LIN have a few lights on the front of the housing.  You should notice a USB LED on your device that lights up when you plug it in.  The USB LED will be orange if you have a USB high-speed connection (USB 2.0) and green if you have a USB full-speed connection (USB 1.0). 

The CAN or LIN LED does not indicate the functionality of the device. It indicates when the device is sending data to the bus or receiving data from the bus.

Additional Information

To test the functionality of the device, try running one of the examples found in the example finder.  If a message is successfully sent or is successfully received and acknowledged, the network light will light up.  This light will only stay lit as long as data is being sent or received, so the light is expected to flash.

It is important to note that to run these examples, another port on the bus must be configured to either accept the sent message and send an acknowledgment or the other device must be sending information to the bus.