# Flash of 1 pixel when powering on - normal?

**URL:** <https://wled.discourse.group/t/flash-of-1-pixel-when-powering-on-normal/1362>\
**Category:** Hardware\
**Created:** [November 21, 2020, 10:55am UTC](https://wled.discourse.group/t/flash-of-1-pixel-when-powering-on-normal/1362 "2020-11-21T10:55:11Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![matt-uk](https://avatars.discourse-cdn.com/v4/letter/m/e5b9ba/32.png) [@matt-uk](https://wled.discourse.group/u/matt-uk)\
**Post date:** [November 21, 2020, 10:55am UTC](https://wled.discourse.group/t/flash-of-1-pixel-when-powering-on-normal/1362/1 "2020-11-21T10:55:11Z")

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Not sure if this should be in hardware but appreciate any feedback please.

I have a string of ws2811 square pixels. 12v controlled through a DigUno and ESP 32 Mini with plenty of amps/watts etc.  
I have WLED to leave the lights out when powering up, however I find that when I turn the power on the first pixel in the string flashes green for a second.

This isn’t a problem in itself but is it a sign of an issue somewhere? The connections were made at the top of a ladder in the rain so I am on the look out for any signs that something isn’t right and I need to revisit the connections. It may be the controller is the issue or maybe it is completely normal.

Any thoughts or advice before I spend hours tearing everything apart?

Thanks  
Matt

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**Author:** ![Aircoookie](https://yyz2.discourse-cdn.com/free1/user_avatar/wled.discourse.group/aircoookie/32/2_2.png) [@Aircoookie](https://wled.discourse.group/u/Aircoookie)\
**Post date:** [November 21, 2020, 4:24pm UTC](https://wled.discourse.group/t/flash-of-1-pixel-when-powering-on-normal/1362/2 "2020-11-21T16:24:34Z")

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Hi Matt,

don’t worry, this is normal. Before WLED initialized the LEDs, there may be some undefined/random data on the LED pin, causing one or the first few LEDs to light up for a moment 🙂