Problem w/tk11-r2

I bought a TK11 Cree R2 from j2ledflashlights.com after searching CPF to confirm they were a reputable dealer.. The flashlight worked great until yesterday when I noticed it would work only in 'low' mode. After searching CPF some more and trying the various fixes recommended by others for the same problem and concluding it must be a hardware problem, I tried contacting j2ledflashlights.com... E-mail is bouncing because their mailbox is full. Their phone forwards immediately to voicemail with no announcement and a full voice mailbox. To me, this smells like a company that has gone out of business, not 3 weeks after I received my flashlight..

Does anyone know anything specific about what happened with these guys? Or is this just a temporary aberration?

When the batteries are low, only low mode will work, even if the head is tightened. Try putting in batteries that you know for SURE are fresh, and see if you have high mode again. I use protected 123 cells so I never even get this low-mode-only when the batteries get low, mine just shuts off without going into low mode. I did notice when I use 18650 or cr123 primaries, towards the end of the battery life, you will only have low mode as I mentioned.

Thanks for the reply.

The 18650 that was in there since I bought the light was at 3.74V as reported by my Fluke. My other two 18650's were fully charged at 3.77v. The flashlight works the same regardless which of the three batteries I try in it.

I also tried tightening the bezel all the way, then inserting the battery and then the end-cap per another suggestion. I also cleaned the ring contact with some light emery cloth per yet another suggestion.

Still unable to get in touch with j2ledflashlight also.

Wow, that sucks... Sounds like there's definitely a problem with the light. I have no idea what's going on with j2led, but maybe you could try the warranty directly through Fenix. It should still be giving a high mode on a fresh 18650.. How about for sh*t's 'n' giggles, could you try out putting in fresh 123's? Maybe the higher voltage will allow high to come on, though there's still definitely a problem with 18650's and no high...

Those voltages sound really low. Fully charged lithium ions should be around 4.1-4.2 volts. Less than that means either the charger or cells are bad.

Yoda4561 said:

Those voltages sound really low. Fully charged lithium ions should be around 4.1-4.2 volts. Less than that means either the charger or cells are bad.

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+1. Yoda's right, I always see 4.2 volts on fully charged 18650's...

+1 !

~4.2V on AW 18650 protected freshly charged.

3.7V with no load is about dead. I haven't seen a runtime graph on the TK11, and don't know if it's fully regulated with a 18650, but if your batteries are reading that after charging, the charger may be the suspect.
For instance, the last time I checked runtime on a light with Li-ions, I measured the batteries' voltage after an hour, and they were 3.64V with no load. Less than 5 minutes runtime later, the protection mode kicked in.
All my Li-ions measure between 4.18 and 4.2V after charging.

hmm. The datasheet for the batteries says 3.7V:

http://www.panasonic.com/industrial/battery/oem/chem/lithion/

Even the datasheets for AW18650's says 3.7v as well which is why I thought they were fully charged...

I'm not arguing; just confused. I'll go out and buy some CR123's and see what happens I guess.

3.7 is the nominal load/operating voltage. All LiCO (most common) and LiMn(aw IMR/powertools) are 4.2 volts off the charger, open cell voltage. Batteries in good condition will hold that voltage for months if not used in a device. If the open Cell voltage is 3.7v or less they need a recharge. If it is less than 3.5 volts it's very dead and should be recharged immediately to prevent battery damage. Same deal for most rechargables, nicads and NiMH batteries aren't actually 1.2 volts off the charger, they're around 1.4

It can be confusing.
3.6 or 3.7V is generally given as the nominal voltage. In practice, they're 4.2. The rechargeables listed as "3V" are actually as high as 3.6V after charging, and hence unsafe for 6V incandescents(which are really 5.something) even though you'd think they would work given their designation.

garnish said:

hmm. The datasheet for the batteries says 3.7V:

http://www.panasonic.com/industrial/battery/oem/chem/lithion/

Even the datasheets for AW18650's says 3.7v as well which is why I thought they were fully charged...

I'm not arguing; just confused. I'll go out and buy some CR123's and see what happens I guess.

Click to expand...

Even if your batteries are empty, they should be able to power the light in turbo mode at least for a short burst. I tried with mine by using a empty 18650. It lights up for second then switches to "moon mode".

Your light is probably damaged...

3.7v open circuit is definitely less under load.

You're using dead batteries, try charging them up...

John, the owner of j2ledflashlights.com, is at a tradeshow in HK right now - I think he'll be back in a week or so IIRC.

I had the EXACT same problem with my TK10 I used it in high for about 5 minutes put it back on the shelf next day it just refused to go into high mode completely I had to send it off under warranty, I emailed fenix and they said it was a circuit fault, seems to be quite common by the looks of it.

ok. I charged one of my batteries up to 4.19 and still no 'turbo mode'...

I guess it's good news that John's out of town. I'll keep trying then.

What happens when you tighten and loosen the head??

This still does not allow me to post does it, i had the same issue with the TK10 seems like a common fault, the circuit just fails for no real reason.

When I loosen the head, nothing happens. It stays the same brightness (low) for a few turns... It used to be a half turn from high to low.

Garnish,
Please email my employee Emily at [email protected]. She can handle the warranty for your defective light. Sorry for the inconvience in trying to reach me. Yes, I am visiting trade shows right now

thanks
John
j2ledflashlights.com