LiteFlux LF5XT Died

While traveling I removed the battery from my LF5XT for a week to prevent accidental turn-on while in baggage (and rotating another light as my EDC). After inserting a freshly charged AW 14500 (polarity correct) it appears to have basically died. After some clicks I can get it to turn on at a low light level (but won't turn off), and sometimes it puts out a single bright flash. Any ideas on how to best diagnose any simple problems which might be causing the problem?

Have you tried any other batteries? It's possible there's a problem with the battery...

I agree. It sounds like a bad battery. The periodic flash may be a sign that the voltage on the battery is low. While in low, Click (C) 5times to get a voltage readout of the battery as the flashlight sees it. (see your instructions for how to read it)

Tried two different 14500's fresh out of the charger. Both these batteries worked fine in my Nitecore lights but not in the LF5XT. Also tried a fresh alkaline cell and charged NiCd and got the same results.

The light isn't really responding to clicks, so the normal 5 click function to get battery voltage doesn't do anything.

Did you try reseting it?

Erm... If he says it's not responding to clicks, he obviously can't reset it either.

Have you checked the innards? The tube, the contacts, the tail cap. Especially the brass ring around the spring in the tail cap. Do they look ok? Did any lube get on them?

Does the clicking sound/feel the same as before?

Maybe the brass sleeve doesn't contact with the brass ring of the circuit board properly.
There are two notches in the periphery of the circuit board. Insert tweezers into these two notches, then rotate the circuit board counterclockwise with tweezers for 1/4 ~ 1/2 turns.
And check if this remedy is effective.

orcinus said:

Erm... If he says it's not responding to clicks, he obviously can't reset it either.

Click to expand...

It may not, but that's not a good way to go about trouble shooting. You don't just not try something because something else didn't work. He should try resetting it, and if that doesn't work, he can check that off the list of things to try. That way when he contacts Liteflux and they say "Did you try resetting it?" he can say "Yes I did." rather than "Uh, no." Maybe he has already tried to reset it, but I didn't see him mention that.

Could a light like the Liteflux have been damaged going through airport x-ray machines, etc?

can you change mode when it is on? or do a PH or C + PH?

try tightening the on/off switch retainer ring in the tailcap.

khoo

Does not respond to the normal C + PH and all that stuff that allows you do make this light do all of it's neat things. Getting into the menu's that allow reset mode is impossible. I've tried loosening and tightening all the working parts. It didn't go through an X-ray - happened during a very short bit of car travel. Was really just wanting to rotate my EDC and have found that the absolute best way to make sure a light doesn't go on unexpectedly while packed is to remove the battery. The switch sounds the same, but tonight I'll put a meter on it to confirm it's doing it's job. Will also look at cleaning everything latter on (but nothing looks out of the ordinary from a quick inspection.

Many thanks for all the suggestions. Want to be absolutely positive of it's failure before going through the hassle of sending it back.

WadeF said:

You don't just not try something because something else didn't work. He should try resetting it, and if that doesn't work, he can check that off the list of things to try. That way when he contacts Liteflux and they say "Did you try resetting it?" he can say "Yes I did." rather than "Uh, no." Maybe he has already tried to reset it, but I didn't see him mention that.

Could a light like the Liteflux have been damaged going through airport x-ray machines, etc?

Click to expand...

That's not what i wrote nor meant. It's not a matter of giving up or not trying something else, it's a matter of prime prerequisite for what you're suggesting completely missing.
The OP said clicking DOES NOT work. As in, he can't get to the function menu nor select factory reset from there. In fact, he said it does not respond to clicking at all after he gets it to turn on.

Re: airport x-rays - it should be ok. Today's machines are pretty much safe for anything electronic.

@OP - the way i see it, either your switch PCB is askew or not tightened properly, or your switch has gone crazy, or you're losing (switch signal) contact somewhere. Or your LF5XT has simply gone bonkers and is beyond user serviceability.

Try Eneloop aa.
Turn over-discharge protection on.
Then put 14500 back in the light.

Bummer. Strange how a week with no power hurt the light. I wonder if this is a common problem with this light? I have allways kept a cell in the light...
I suppose it is possible (but unlikely) that it just needs to sit for a while with a battery installed. Maybe that will kickstart the MCU...
Ummm
Yaesumofo

orcinus said:

The OP said clicking DOES NOT work.

Click to expand...

Actually he said:

"The light isn't really responding to clicks," and "After some clicks I can get it to turn on at a low light level (but won't turn off), and sometimes it puts out a single bright flash."

So I was wondering if it's somewhat responsive, maybe clicking through the sequence to initiate a reset might take, even though I'm pretty sure it won't help. I was just throwing out a suggestion.

Took apart the main subcomponents and cleaned everything with a kimwipe. No more than a spec of some foreign material on the inside of the tail cap switch caused the problem. Could hardly see the spec - really needed a magnifier to see it. All is working fine now.

Thanks to all you good people out there in this community for your suggestions. Feel kind of silly it was such a simple problem, but still better than sending it back. BTW - khoo was right there ready to support me. He is a great vendor.

Just a followup to your LiteFlux that died and now is revived. I had a similar thing happen to me this evening with my new LF5XT, only a day old. I changed batteries from an Eneloop to a good newly charged 14500 cell and the light would not turn on at all, even though all was tight at the endcap and head. I put the Eneloop back in and still totally dead. Well, after reading your thread and looking at Khoo's suggestion, I looked at the retaining ring in the tailswitch. It was quite loose and after tightening it a couple of turns, the light worked better than ever.

How better than ever? Well, even before the light would not turn on at all, I noticed on occasion that I needed to hit the tail switch twice before it would turn on. I attributed this to the MCU going to sleep with disuse and not responding with the first click quick enough to turn it back on. Well, I have a feeling the problem was this loose retaining ring, all along. It could have been loose from the factory. However, it may have loosened because I was loading batteries from the tail end. I suspect as I unscrewed the tailcap to change the battery it further loosened the retaining ring. Besides tightening the retaining ring, I think the best way of avoiding this problem in the future will be to always load the battery from the head end. Hindsight is 20-20.