ESP8266 resets after 1 hour, nearly everything else works

Hi Folks!

The situation

I’m using a Lolin D1 Mini pro with WLED 13.2 installed to control a string of fairy lights which has 200 leds (It’s one of the ones that have each led’s number ‘baked’ into the led. Led 21 will always be Led 21, regardless of where the string is cut). Originally it came with a usb controller/power supply, that I cut off.

I am using a 5V 2A usb phone charger to power it, with the positive going to the D1 Mini’s 5v pin and the LED’s positive wire, and all the grounds are connected together as well.

Currently I have 2 470uf, 16V capacitors (they were what I had on hand) in parallel connecting the 5V and ground from the power cable. I’m honestly not sure if they have made a difference.

I am using the current limiter in the led settings to about 1600ma right now, which leaves the leds bright enough for my use.

No level shifter as the first led is not too far away.

The leds are run as 4 segments, with different number of leds, different colours, different effects. Not all leds are in a segment, and are just blank. This is save to a preset that is loaded on boot.

I am also using the home assistant integration.

I have tried WLED 12, 13.1 and 13.2.

What works

  • All the leds in the string
  • I am connected to my home network by wifi
  • The web interface works
  • Effects work
  • Home assistant control works

The issues

Everything would be perfect, except for, well 2 things now.

  1. The board will reset every so often. The last one I saw was exactly 1h uptime before reboot. I know it is reboot as the leds will go back to the starting preset. If I have the WLED ui open, it will briefly show that it disconnected. This is by far the most annoying issue.

  2. As I discovered as I was writing this, I can use the web ui on my pc to turn segments on and off. If I use the phone app OR the web ui on my phone to do… anything… with the segments it will crash the wifi connection. Phone and PC will be disconnected, but any currently running effects keep working.

Hopefully that makes sense, sorta typed this out in a rush. Does anyone have any ideas?


  • Trying a 3A phone charger, with the current limiter set to 2A. Still reset at ~56 minutes
  • Still resetting, most recent at ~15 minutes, going to try a different 5V 2A power supply that has a barrel jack instead of a phone charger. Have ordered a 5V 6A power supply from ebay.
  • Made it nearly 2 hours this time with 2A power supply, limited to 1A in ui. Still resetting.

My first guess would be you’re betting on your power adapter being able to supply 2A continuously and/or that the brightness limiter is more accurate at measuring power usage than it is.

The ABL doesn’t actually measure anything, it’s just a calculation based on what you tell it about your LEDs.
Try knocking the limit current back to 1200mA, or better yet, get a proper 5V power supply.

Those fairy light LEDs can take a good deal more power than the USB connection allows for. They manage their power usage with the controller and effects they provide. WLED gives you much more control but also creates scenarios where the power draw is appreciable.

Remember that the D1 will also need a good power source as well. I’d suggest you get at least a 3A supply or better yet a 5A. You could also try and run the D1 from a separate supply than the LEDs, just make sure the ground is common between the 2 supplies.

Honestly, it hadn’t occurred to me that I couldn’t trust my generic found in my draw 5V 2A phone charger… Perhaps it should’ve, but I was just taking it at it’s word.

Okay, I’ve swapped in a 3A charger… that I also had lying around, and set the limit to 2000mA. We shall see how that goes.

When you say proper power supply, would this do? (A first result on ebay for 5V 5A)

I really don’t need that bright, just trustworthy to stay doing what I left it doing. Which reminds me, I’ve had it wake me up in the middle of the night after a reset, when the leds were off originally, so current draw should have been fine?

2 power supplies is an option that I’ll hold in reserve for the moment, but it is good to have an option again.


I have my 5V 6A power supply from the ebay page I linked. I bought 2, first one rattled and didn’t really work. Not a great start, but the 2nd was fine.

I’ve made it to 3hours before a reset now, once.
Using WLED app or webpage on mobile still crashes entire thing. I’ve discovered this only really happens when I have 4 segments.
NEW ISSUE: Since switching to this new power supply, the first 25 or so LEDs will flicker UNTIL I turn on more LEDs later in the string. Again, this is the first 25ish, so right next to controller and power supply.

Okay, last update. I started over using an ESP32 instead of ESP8266, and all my issues went away. Not sure if its a bug, or if I just had dodgy boards (I do have another ESP8266 running fine), but running 5 days strong on the ESP32.

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