odd behavior of Fenix L2D ... failure?

[AlexK]

Recently, I noticed twice the same odd behavior of my Fenix L2D (P4-version):

When playing around with it and after turning it off, the light turns on in the low mode and refuses to change to a higher mode. Turning the head for turbo doesn't change anything, still on low.
Every half-click of the switch causes the light to flash once, but it stays on low.

After leaving the light off for a couple of minutes, it seems to recover and works as it was meant to.

My first simple assumtion was, that the light was overheating and some thermal protection kicked in. However, the light seemed only slightly warm to me, when the failure occured.

Has anyone noticed a similar behavior? Do you think this is still o.k. or do I own a flawed version? :shrug:
Since the problem seems to resolve itself after a while, I can still use the light, but it bothers me to have a light which might not be fully reliable.

Greetings from Germany,
AlexK

 

[DanielG]

Guten Tag!

How many hours have you used those batteries? Could they be dying?

 

[Lobo]

Yep, what DanielG said. I've been noticing the same behaviour when the batteries are getting low and can only power the lower modes.
Just switch the batteries, if you still have the same problem, there might be something fishy going on.

 

[WildChild]

It's not a thermal protection, it's a bug in the UI. Sometime it can get stuck in turbo mode and twisting the head or half-clicking won't change anything. After leaving it off for a few minutes, again it recover. It happens when the light switches fast between turbo mode and low mode, many times, like when the head is just at the point it will contact to go to turbo but it won't stay there. Rule of thumb, when you go to low mode, unscrew the head at least 1/3 turn to go to low mode so it won't accidentaly touch the turbo mode contact point.

 

[AlexK]

Wow, you are fast in replying! :thumbsup:

I forgot to add:
after the low-mode-only-behavior occured, I changed to a set of fresh Eneloops ... still the same, only low mode available.

WildChild, do you mean the UI gets stuck in the turbo-mode sometimes?
Maybe the UI-bug is similar. I think I remember using the low mode extensively before it occured, so maybe mine just got stuck in the low mode.
Do you know if Fenix might have improved the circuit in the Rebel or Q5 versions?

 

[mchlwise]

Have you checked the tailcap and made sure it's tight and the switch retaining ring is tight?

My P3D was doing something kind of similar the other day, and I realized the tailcap wasn't tight.

:shrug:

 

[Julian Holtz]

Moin!

Also make sure, that the round aluminum thing with the 2 holes, inside the tailcap, is screwed in firmly.
---
Too late, previous poster said it all.

 

[WildChild]

Wow, you are fast in replying! :thumbsup:

I forgot to add:
after the low-mode-only-behavior occured, I changed to a set of fresh Eneloops ... still the same, only low mode available.

WildChild, do you mean the UI gets stuck in the turbo-mode sometimes?
Maybe the UI-bug is similar. I think I remember using the low mode extensively before it occured, so maybe mine just got stuck in the low mode.
Do you know if Fenix might have improved the circuit in the Rebel or Q5 versions?

With mine it once got stuck on a single turbo mode and once on a single very low mode. With this very low mode, I kept it on and the brightness diminished at a point where the die was just faintly glowing! I had to keep it off to reset the circuit.

See there:

http://picasaweb.google.ca/picasawildchild/L2DBug

 

[Juicespeare1]

I posted this yesterday and received no responses:

http://www.candlepowerforums.com/vb/showthread.php?p=2188818#post2188818

================================
Electronic problems with my P2D CE Q2
================================
I bought a P2D CE Q2 from the Fenix-Store a few months ago.

I'm happy with the model, but have been seeing a few issues electronically.

I've had this happen numerous times now (using fresh primary battery, Surefire brand only):

1.) I turn the light on in low mode.
2.) Depress the tail switch, the light flickers (high briefly like it normally does when switching modes) and remains in low mode.
3.) No amount of pressing/releasing the tail switch will put the light in medium mode or high mode or SOS mode.
4.) Even when turning the head to tighten to go to Turbo mode the light remains in low mode and no amount of pressing/releasing the tail switch will change the mode to turbo or strobe.
5.) The battery is fresh.
6.) To get out of this mode, I have to turn the light off for at least several seconds (maybe 10-30 seconds or more).
7.) After light has been off for several seconds (10-30 seconds or more) and the light is turned back on the light will work normally again. I can switch between low, medium, high, SOS, then tighten the head for turbo and strobe.

This has happened numerous times now over the last few months. It's not a fluke kind of thing.

I don't know what causes it, only that turning the light off for a period of time resets something in the electronics and allows the light to work as normal again.

Any ideas?

 

[Juicespeare1]

Yep, this has happened on mine a couple of times too, except it started out in low mode (or maybe even lower than low) and the light output diminished very quickly over a few minutes to barely glowing. I thought the battery or LED was dying, but nope. After a few minutes of being off, the light started to work fine again and the battery was still very good, like new.

With mine it once got stuck on a single turbo mode and once on a single very low mode. With this very low mode, I kept it on and the brightness diminished at a point where the die was just faintly glowing! I had to keep it off to reset the circuit.

See there:

http://picasaweb.google.ca/picasawildchild/L2DBug

 

[ltiu]

1) Clean all contacts, head and tail.

2) Use new batteries.

 

[Juicespeare1]

Nope, not the issue, this is something in the electronics acting up. The threads and battery are fine. After the light sits off for awhile it begins to work properly.

Turning off the light for awhile resets something in the electronics/logic.

1) Clean all contacts, head and tail.

2) Use new batteries.

 

[Lobo]

Weird, I haven't had any kind of problems like that, and I have used my L2D extencively. Allthough it can act a bit weird when the batteries are low.
One other thing is that I dont have the flash between levels either (at least nothing that I notice), are there different versions of the circuit or something maybe?

All in all, the more reason that Fenix should release more 2 stage lights like the LxT series and skip the overly complicated UIs!

 

[etc]

No such behavior for me. Mine just completely/suddenly died. I had the vendor replace it, so I am happy, FWIW.

 

[Bort]

One other thing is that I dont have the flash between levels either (at least nothing that I notice), are there different versions of the circuit or something maybe?

I have an L2d ce that flashes in low mode, and a P2d that doesn't flash in low mode. I swapped the heads, and no change with the different battery configurations. I must have two different circuits in the heads.