Constant Low Battery alert and saber not igniting


I have a Proffie 3.9 and for some reason, I keep getting the low battery alert when turning on the saber. I have used a multimeter on the battery, as well as the board pads themselves and I am reading at around 4.1v. I have re-wired the board around 5 times now and purchased a new battery, but I still get the same message. When installing the fresh battery, the saber will light up and work fine for around a minute. Once you cut it off, it will not light back up. It will just make the ignite sound but never actually light up. I have noticed that when the saber is actually lit the first time, after a little bit, it will start beeping then that’s when you are unable to get it to light back up. I have looked over all of the components on the board and nothing looks to be burnt or shorted.

This is my first neopixel build and it has been a headache so far haha. Any help is greatly appreciated.

Thanks so much.

What type of battery are you using? Voltage is only half the story - you need a battery that can discharge sufficient power rapidly enough to drive 250 LEDs all at once, which comes to quite a few amps.
Does the problem happen with no blade in the hilt?
Does it happen on all colours?
Does any part of the Proffieboard get hot?
Might be worth posting your config here (use, and maybe a couple of photos too.

Great questions. The battery that I am using is the KeepPower 15A 18650. Yes, the issue still happens when there is no blade in the hilt. Yes, the issue happens on all colors. I am not positive on any parts of the board getting hot. I will check that and get some pictures once I get home. Here is the config though…

Proffie Config -

What does the serial monitor say?

In general, if you’re reading 4.1v between BATT+ and BATT- on the board, at the same time as the board is reading a much lower value, then there is something wrong with the board and you should ask the seller for a replacement.

Note that “at the same time” is important, because if your wiring or your battery is bad, then you might have 4.1v between BATT+ and BATT- until you turn something on, and then it drops significantly.

Thanks for the reply! I checked the serial monitor and I have attached what I am seeing while the saber is on and the battery is in the chassis. While I was testing, I noticed that the blade would ignite until the board started beeping then it would shut off and not light back up. Also, I can twist to ignite while the battery is only powering the board and the speaker inside of the lower chassis and it would still give the low battery warning and never stay on and “humming”. I have attached the results of the serial monitor, the lower chassis, and a close-up of the board itself. If you need to see the other side of the board just let me know and I can de-solder everything and take it out.

I don’t know if it matters, but when it did work, the speaker sounded “crunchy”.

Thank you all again. I really appreciate you working with me on this.