Error -1074388981: CAN Bus Communication Is Off

Updated Nov 22, 2022

Reported In


  • NI-CAN

Issue Details

When I try to run my program using NI-CAN or NI-XNET program, I get error -1074388981 stating that there is a problem with the CAN bus.  The error states that the CAN bus is in the CAN Bus Off state as shown below. 

I have verified my cabling is correct, devices are connected and operational, and proper bus power is applied. Why do I get this message and how can I resolve this issue and get my hardware working?  


This error occurs because the bus recognized a fault and went into a Bus Off state to protect the hardware or because the bus is not properly configured.  You will want to go through the following steps to verify that everything is working properly.
  1. Make sure the NI-CAN devices are powered properly and connected properly to their interface (i.e. USB, PCI, PXI)
  2. Verify that you are supplying the appropriate voltage to the bus if the CAN bus is externally powered.  
    • For High Speed and Low Speed CAN, the external voltage should be between 8 - 27 VDC (12 volts typical) as referenced from V+ to V-.
    • For Single Wire CAN, the external voltage should be between 8 - 18 VDC (12 volts typical) as referenced from V+ to V-.
    • For additional specifications including expected current draw, reference the NI-CAN Hardware and Software Manual.
  3. Verify that the the CAN_H and CAN_L data lines are not shorted together.  If there is a short between these data lines, this error will be generated.
  4. Verify that you are using an appropriate cable to interface your CAN devices.  For example, a serial RS232 cable looks similar, but is not compatible.
  5. Check if there are other devices on the CAN bus and if they are functioning properly.