Hi,
I do have a Strong light flash when powerup Ledstrips.
I have this unwanted “effect” with all strips WS2812, WS2815, APA102.
No matter if I use level shifter, even capacitor from 1000 uF connected on power and/or 330 Ohm resistor on data line.
After the strong light flash everything works fine.
Any clue how to fix this?
This is likely due to the boot-state of the pins used (depends on which micro you are using). It’s another reason to use the relay mentioned in the code to switch LED power.
Hi Tonyo,
I am using a Wemos d1 mini.
I do not know exactly what you mean with “relay mentioned in the code”
(I Use always the *.BIN file to update)
Unfortunately I have no space left for a Relay.
The unwanted problem doesn’t occur when turning on with the app, but only when turning on the main power. (what I prefer because I have the power connected to a Z-wave power switch)
When I use an arduino nano (with another script of course) I don’t have this unwanted “effect” of an Strong light flash when powerup Ledstrips.
So, Isn’t there another way to solve this problem? 
BTW, thanks for your help.
You could try using a bin compiled for another pin, only the UART pin causes the flash I believe. Try the DMA pin if you do not exceed the LED count limitation of 500 (best if below 300).
What did you mean by
Unfortunately I have no space left for a Relay.
Does that mean you have no free pin left or you have no physical space?
Thanks Brentbrooks for youre reply,
The LED strip is connected to GPIO2 (NodeMCU/Wemos pin D4 ) like described in Quick start guide .
I have no Physical space left for a relais.
Small video of this unwanted “effect”: Click here
I still have a Strong light flash when powerup Ledstrips.
I tried WLED_0.9.1_ESP8266_ledpin4.bin
Instead of the default WLED_0.9.1_ESP8266.bin
So Data pin GPIO4 (D2) On WEMOS D1 instead of the default GPIO2 (D4)
(I know it sounds confusing, so I refer to the picture above which shows the pinsettings from WEMOS D1)
I have several different LED strips (WS2812, WS2815, APA102) with all the same problem.
Resistor 330 Ohm on data pin didn’t help.
Big capacitor (from 1000 uF) on power line LED strip didn’t help.
Level shifter didn’t help.
Neither another pin GPIO4 instead of GPIO2 did solve the problem.
But I still have this Flash when powering on…
Am I the only one?
I want to turn it on/off by power adapter connected to wall plug, so in case of Not using the LED strip there is no power consumption left by the power adapter.
Yeah, as mentionned, that’s because of the boot state. If you only connect power to the leds, with no signal, they will light up bright white.
I’m looking to see if I could use a computer PSU with the 12v being remotely activated by wled at the same time as the leds. I just asked the question on another thread.
In my case the Leds will not flash or light up bright white, if data signal is not connected.
But I agree that it has to do with the boot state.
So now I try to make some kind of delay between the positive power of the LED strip and poweradapter.
Made some drawing:
But I don’t know how to offer a delayed signal to the Yellow Wire.
Who knows?
An RC circuit, with a resistor and capacitor, like this: https://www.build-electronic-circuits.com/rc-delay-element/
Thanks for your reply huggy-d1,
Tried the “RC delay element” from your link, but it didn’t work.
Think I solved the problem with 555 Timer delay
So my first drawing becomes something like:
I just tested it on a breadboard with an SRD-05 relay on leg 3 of the 555 timer (instead of a single LED) and the delay worked.
Tomorrow I will actually try it on my LED strip.
For now a 
to celebrate.
A relay was mentioned at the beginning, couldn’t you use that? There is a pin that goes high when wled lights up the leds
