# Troubleshooting Green LED Failed polling LED status error on MiSeq

In MiSeq Control Software v4.0.0, some runs have a notification message: **GreenLED: Failed polling LED status.**

The message typically does not stop the run, nor impact run performance, and is usually due to a communication issue on the instrument.

![](/files/ziUogsRMcOvyzkjzl9Sf)

**Troubleshooting Steps**:

1. Contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support) for instructions on how to upload the compressed folders to a secure FTP site for review.
   1. From within D:\Illumina\MiSeq Temp\[RunFolder]\\\
      InterOp folder\
      RunInfo.xml\
      RunParameters.xml\
      Cycle Logs (found within D:\Illumina\MiSeq Temp\[RunFolder]\Logs)
   2. From within D:\Illumina\MiSeq Control Software\
      Logs folder
2. Power cycle the MiSeq **after** the run completes.
3. If the instrument initializes successfully, continue using it for sequencing and monitor the next run.
4. If the instrument fails to initialize, contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support).

For further information, search for Knowledge Base articles [How to Power Cycle the MiSeq](https://knowledge.illumina.com/instrumentation/miseq/instrumentation-miseq-reference_material-list/000001894) and [How To Power Cycle the MiSeq Video](https://knowledge.illumina.com/instrumentation/miseq/instrumentation-miseq-reference_material-list/000005871).

\
\
\ <br>

|                                                                                                                                                                                                                                                                                                                                                                        |
| :--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------: |
| *For any feedback or questions regarding this article (Illumina Knowledge Article #5382), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000005382%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://knowledge.illumina.com/instrumentation/miseq/instrumentation-miseq-troubleshooting-list/000005382.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.