# Troubleshooting Pressure decay or Impedance test stopped with NaN results on the NovaSeq 6000

If Pressure Decay or Impedance test on the NovaSeq 6000 system check stops with NaN result:

* **Check pressure sensor readings:**

  * Close NovaSeq Control Software.
  * Open NovaSeq Service Software (NVSS).
  * Navigate to Integrated Chassis Assembly.
  * Navigate to the Sensors Tab and select the refresh icon for Fluidics.
  * If any sensor is >2.5psi, take a screenshot or picture of the result and collect NovaSeq Service Software Logs located under C:\ProgramData\Illumina\NovaSeq\NovaSeq Service Software\Logs and contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support) for the next steps.
  * **Note**: Pressure sensors are not used during a run and, therefore, failing sensors will not impact a run performance. The instrument can continue sequencing until an Illumina Field Service Engineer (FSE) can replace the sensors.

  ![](/files/SPbIYN7sM1JvgyOt1nD5)

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #2492), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000002492%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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