This flash is about 6 months old. It has begun to act as if it has a defective switch.
But I’m wondering if perhaps it’s design needs a certain voltage or current threshold to light the LEDs at all.
The batts check good, but they are borderline 1vt each.
Defective switch?
Get your money back from your homies! 
Try new cells first- at 3V unloaded they may not be enough under load as cell voltage drops with load.
Phil
thanks for the visual. as I was thinking.
Don’t mean to thread jack, but does anyone know how to get to the driver and emitter? I’m trying to switch out the LEDs with some XPL HI, but cant find a way to get at the driver and emitters.
Is this the 3C we were getting here a couple of years ago with the XM-L2 and large reflector?
If so I can post some tear down pics later today.
Might help you as well OP if it turns out to be a bad switch, the come apart easily and the drivers are super simple, a small FET and a couple of resistors IIRC.
I’ve got a similar mod in the pipeline, albeit an XHP35 HI in lieu of the XP-L HI. The heat sink is sizable for a Chinese light and should handle it well.
-Michael
I believe so, definitely a 3c, but the triple led emitters don’t seem like XM-L2s.
batts were the issue. now I have a strip of Cs.
oh well, that was short lived. I guess the switch is bad.
It’s a Homies special Defiant HD15BF01 850 lum.
just for s&g, I removed and re-installed the switch module. So far …………
yup, thats the one I got, but i honestly don’t think they are XM-L2s. I can get the head of the flashlight loose, but the reflector/pill is keeping it from coming out.