Archived:Troubleshooting an SCXI Measurement Issue

Updated Jun 12, 2023

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Reported In


  • SCXI-1001

Issue Details

I have an SCXI system that has worked properly for years in the past. However, recently, I am no longer getting expected measurements. What are some troubleshooting steps I can take to diagnose and solve the issue?


The following steps may help to isolate or solve the issues with your SCXI system:
  • Try rebooting the PC
  • Try reinstalling PXI Platform Services and DAQmx
  • Try switching which slot houses the DAQ card your SCXI chassis is connected to
  • Try plugging the DAQ card into a different SCXI card, or moving the SCXI card it is connected to
  • Try using a different DAQ card
  • Try using a different SCXI chassis
  • Try using a scope to verify whether the voltages going into the SCXI card match what you see in software
  • If your SCXI card supports it, try communicating with the card using parallel mode. This is describe on page 74 of the SCXI Getting Started Guide. This allows you to communicate directly with an SCXI card bypassing the SCXI chassis for much of the communication.

Additional Information

Often, as SCXI chassis get older, they exhibit odd functionality changes when the backplane becomes more electrically worn. If you have isolated the issue down to a specific card or the chassis, you will likely need to either replace the chassis or send it in for repairs. If this is the case, it may be a good time to consider upgrading from an SCXI system to a PXI system, as SCXI repairs are often expensive. Contact NI Sales if you would like to discuss this option.