What could cause a flashlight to turn itself on?

LED Flashlights – General Info
1

Wondering if anyone has some insight on what could cause a flashlight to turn itself on. Driver issue, damaged emitter? And no i’m not talking about in my pocket.

2

Some AA lights turn themselves on if you shine a light at them

3

When some flashlights get very lonely, they tend to turn themselves on.

4

Ha ha. This light could have easily caused a fire in my house if I had not smelled the cloth it was sitting on melting from the other room.

5

Is it a e-switch or a tail switch light?

6

What light was it and which battery?

7

If the negative wire to the MCPCB grounds out I’m pretty sure it’ll go to direct drive.
I’m usually wrong about this technical stuff, I’m just an emitter swapper, but I’ve seen it on lights where folks have stuffed other stuff in to try to replace a P4 style emitter.
What model of light is it?

8

Brand new E07 Cu/Ti with a LG HG2 18650 with provided sleeve adapter.

9

My Olight S1A turns on if the sun shines on it.It took me a while to figure it out but it happens every time the sun shines through my window .

10

How’s that happen? Never had a light turn on by itself for me

11

Found this upon further inspection. Seems there might not be enough clearance in the head for the optics. The light was sitting untouched for over 12 hours.
Light

12

Yes it’s a known, uh, feature. Caused by UV light. The LED is working in reverse, like a small solar cell, and the driver takes that as input.

13

I had a defective Olight S1A that did this, randomly turned on by itself. Not because of shining UV light on the LED.

14

I can’t believe I have to stash my lights away in a place where the sun don’t shine.

That’s too much of a nuisance. I think I’ll stick to locking out per tailcap.

15

I found my P1D turned on by itself. It was because of defect, worn out switch.

16

Yeah and a convoy L6 probably won’t even fit there.

17

Did that flashlight get a peek at the BLF screen while you were browsing?
Seeing all those lovely flashlights is enough to turn any light on.
All those hard aluminum bodies… it’s flashlight porn…

18

I’m just waiting to see if anyone’ll suggest to “stick it where the sun doesn’t shine”.

19

Ah, there we go…

20

Bright light was known to reset early Raspberry Pis.