Comment on page
Troubleshooting Focus Mirror Error on the MiSeq
The following error relates to the M3 focus mirror failing to move during flow cell scanning and leading to a premature run stop.* This error usually mentions the M3 or focus mirror.
- If this component is not working correctly, the MiSeq will not be able to image clusters correctly.
Error Message: FocusMirror: Focus mirror move and/or sensor failed: The FPGA reported an error while executing command "FOCMRRFOC" error message: "Focus Mirror sensor not found"

**Troubleshooting steps:**1. Complete the post-run wash.
2. Power cycle the MiSeq.
3. If the system initializes, run the M3 Mirror Test in the System checks 5 times to verify the mirror moving correctly.
- MiSeq Control Software (MCS) v4.0: From Main Menu, select System Check.
- MCS v3.1 and older: From Welcome Screen, select Manage Instrument, select System Check.
- Follow the prompts on the screen to start the test, and repeat the test 4 more times (5 times total).
- 4.If all five M3 mirror tests pass, continue with the next run.
- 5.If the system does not initialize or any of the M3 Mirror Tests fail, contact Illumina Technical Support for further assistance.
For further information, search for the following Knowledge Base articles:* How to Shut down or power cycle the MiSeq
- How To Power Cycle the MiSeq Video
- System Checks for MiSeq
For any feedback or questions regarding this article (Illumina Knowledge Article #1449), contact Illumina Technical Support [email protected]. |