fix UltraFire torch flickering/mode jumping

I have this with the 5 mode XM-L T6 led in it, and it is VERY BRIGHT!!! (the equivalent of a 1M candlepower spotlight  or a 40W desk lamp) But after a few days playing with it, it started to jump between modes, dim out, flicker etc. occasionally, it would cut out completely Well, I read somewhere a dieing battery causes it. this is not the case. However it does appear the amount of charge in the battery has an impact.

so, me being, ME, I decided to tear apart the torch and diagnose the problem. I looked at the drop-in module... that wasn't the problem. I turned my suspicion to the switch. It seems this was the problem, so I looked around for a replacement, no luck.

my next challenge was to find out how to take apart the tail cap to get to the switch itself.

Step 1: Closer look inside

well, I found out how to take the tail cap apart to the point I can see the inner workings. I drew a simple diagram of what I found, and lied them out in order ( the cylindrical spacer goes inside the other washer / toroid shaped spacer)

Comments

[mirimo]

I made a tool really easily by taking one of the arms off a binder clip and straightening both sides.  

[Jimmy_retro]

Had a faulty switch on my 501b, but this guide helped me sort it! turned out to be a little different internally but i found a misalignment between the tab on the back of the button and the spring to the battery contact. fixed and now works great! thanks!

[-max-]

great! I just wish the Chinese better designed these, i got my light when it was real expensive, I could have bought two maybe even 3 lights for the price I paid for mine, and also, they change the design over time to work better.

[jhoward11]

I have the same problem with my Ultrafire OSRAM LED torch. It is a pretty unique torch...running 3x16850 side by side. Since it is no longer made, and I would never risk sending it to the manufacturer, I'm stuck with trying to fix it myself. I will give this a try and hope that I don't break the light in the process!

[dhartman2]

Thanks, mine had the exact same problem and this seemed to fix it!

[-max-]

great! i figred out with mine, this is a temporary fix. to permanitly fix it, i need to solder the switch ciucuit board to the screw/washer part

[dhartman2]

Thanks for the followup. I noticed a little flickering so I went ahead and soldered mine too, it's been great since. I'm glad, because I spent almost $50 on this light several months ago and it's just been sitting around because I didn't know what to do with it. It was described as putting out 1200 lumens, but I think it's closer to 800. Nice light though, I'm using it as a headlight on my bike.

One additional tip I noticed: After I soldered, I found that the washer didn't need to be as tight as it did before the solder for it to work. If it was too tight, it started flickering again. I think pressure was being applied to the switch causing it to change modes or get stuck in between them. I backed off the washer a little bit and it burned solid for about 15 minutes, even knocking on it a few times. Good enough for me. Now I just need to see if the battery lasts the whole way through a ride, I'm riding a lot more than I did when I first bought it.