Proffie v2.2 Board Only Powers On with USB

Howdy folks! First time poster, looking for some assistance.

I have a Proffieboard v2.2 that I purchased from The Saber Armory about a year ago. Around that time I was able to install it in a neopixel hilt and it worked great for a bit. Then it stopped powering on when I would flip the high amp kill switch (also purchased from Saber Armory).

What is weird is that it will power on just fine and function perfectly IF I connect it to a computer via the micro USB port (along with a fully charged and tested battery installed).

The folks over on Reddit suggested that it might be a ground issue with the buttons or another component. So I have disconnected everything from the board except the negative battery wire, the positive battery wire, the ground wire (which actually just joins up with the ground wires from the buttons), and both speaker wires.

Is it possible something on the board is fried? I’m really not sure what else to look at. I’ve taken a multimeter to every wire I can think to test and everything seems to pass.

Appreciate any assistance. Thanks!

Yes, it’s possible your D61 diode is bad.
To test, plug in USB and boot the saber, turn on the blade.
With the battery engaged, remove USB, the saber should stay on.
kill battery power, then resotre it.
If it doesn’t boot, you likely have a bad D61.
You could also test the diode with a multimeter in diode testing mode.
Searh this site for D61 and see if any of the info is helpful.

This isn’t always the case.
Sometimes D61 just burns completely, and then the saber does NOT say when you remove USB power.

Bummer, I was worried it was something like that. I tested D61 with the multimeter and I’m not getting any output. Seems like that’s the culprit. Thank you NoSloppy and profezzorn.

What might have caused the fault? Just want to learn so that I can avoid any potential mistakes in the future.

Not sure we know what causes D61 to fail sometimes.
Maybe pulling too much power from the 3.3v rail.

Okay, cool. So it sounds like there isn’t a definitive cause for these failures. Again, since this was a DIY build, I’m just wanting to make sure I know what I could have done differently to avoid this in the future. But it doesn’t sound like it was necessarily any error on my part, which is nice to know I guess :smile: