# How to troubleshoot failed to reach target temperature error on the NovaSeq 6000

The NovaSeq 6000 Control Software can report the error:\
\&#xNAN;*The flow cell is unable to reach the target temperature. The run is proceeding, but contact Illumina Technical Support for help*

**Note**: Run will continue to proceed, and generally, there is no or very little impact to run performance or quality.

The possible causes for this error are:

* Transient communication issue.
* An issue with the instrument flow cell heater.

**Troubleshooting steps:**

1. Power cycle the instrument.

* For additional details on power cycle, search for Knowledge Base article **How to Power Cycle the NovaSeq 6000 System?**

2. Perform only *Thermal - Automated Tests* and *Misc - Sensor Status Readouts* tests in System Checks.

* For additional details on system check, search for Knowledge Base article **How to perform system check on the NovaSeq 6000 system**?

3. If system check results pass, proceed with the next run.
4. If either test on the system check fails or the error reoccurs on the next run, contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support).

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