Convoy C8 doing something odd

I was using my Convoy C8 to do some plumbing and had it standing up on its end until it started to run low on battery and started blinking.

So I turned it off and opened it up to put a new battery it. There was a strange smell inside the tube.
I put a new battery in but whereas it would normally turn on when I tighten the end, this time I had to keep it loose to turn on, and loosen up the head end as well as the battery end. It was also stuck in bright mode and wouldnt let me change mode at all.

Whats going on with it?
Has it overheated / shorted? How do I fix it?

Is your new battery the same model as the used one ? Maybe the top is shorting something ? Is the driver clean ?

Does anything look burnt, and is it burnt sort of smell?

Could have been a short. Check the springs, have the gone purple/blue/black coloured and have the shrunk? High heat from a short will do this.

That’s strange. A twisty C8? Does yours have a pushbutton on the end? If it does, and clicking it doesn’t help, plus this:

…sounds like what I had happen once, where the tailcap spring “fell over” because I stretched it and made, effectively, a short between the ‘-’ end of the battery and the flashlight body. Did it blink off while you flashed the switch to try to change modes? If breaking the switch didn’t interrupt the current, look to your tailcap spring.

This thread has been up awhile. Have you had time yet to re-check the assembly of your C8? The pill needs to be firmly screwed in, as does the retaining ring for the tailcap switch. They will unscrew themselves!!

On another, related note: loose pills cause weird behavior like cutting off, flickering, changing (or not changing) modes, etc.

The weird smell could just be leftovers from the manufacturer, or it could be HF gas if you’re using CR123 batteries, but since you used the singular I’m assuming one 18650. Does the smell remind you of anything in particular? Especially something the rest of us could get under our noses?

Troubleshooting is fun.


It sounds like your new battery is too long maybe. Charge your old battery up and try it.

Im using a Sanyo 18650 protected, but I’ve also tried some unprotected (shorter) and its the same.

The smell isnt a burnt smell, its hard to describe. Just very chemically.
It has an on/off push button on the tail end, and a button on the head end to change mode.

best bet is to dismantle the head/tail to see if there’s anything burnt
it could smell different if some weird components overheat

I never knew Convoy C8 has a button on the head. (Because mine don’t have)

It doesn't. OP's light is not C8, C8's don't have side switch... maybe it's L4.

you are absolutely right. I just looked it up in my banggood account.

Its a Convoy L4 Cree XM-L2 1000LM Side Switch LED Tactical Flashlight