Weird Issue: EagTac D3A + Eneloops

Illumination · Jun 29, 2019

Hi everyone, I've got a weird issue with my EagTac D3A Ti that I'm trying to figure out. My D3A works fine when I first put in the batteries. I can turn the light on and off multiple times, switch between brightness with a half click, and switch between modes (L/M/H and Turbo/strobe) by turning the head half turn.

The weird thing is if I leave it aside for a while, then come back, I can't switch it on and off. However if I take off the head again, and put it back, the light is ok again and works as above. It's the strangest thing. I've tried it with a bunch of eneloops of different batches and same thing with all of them. I have not tried with alkaline but I did just get a new 14500 and will try that too.

Some theories:

the fact that it works fine as long as I keep using it and then when it doesn't work I can "reset" it by removing and reinstalling the head suggests it is not the batteries (besides I've tried with multiple batteries, same issue)
the EagTac D3 and related lights have a really useful mechanical dual mode series design where a turn of the head switches between series. As a result of this the light has a "doughnut" like design; eneloops have large buttons at the top of the light; i'm wondering if somehow the large button is sliding and touching the doughnut at the outer ring and it is shorting?
Maybe something is happening compressing the spring enough that the battery no longer makes the right contact? once I open the light does it spring back?

Has anyone else had similar issues??? I've never experienced this with any of the other 50+ lights I've collected over the years. Very weird.

Tac Gunner · Jun 30, 2019

I have two D25A2s and they can act very strangely if the threads or contacts get dirty. I cannot recall them acting like this but I have had them randomly change modes during use, flicker on and off, turn completely off, not get out of low mode, etc.

I use isopropyl alcohol and qtips to clean the threads and all of the contacts. The contacts will get a black haze on them I have found.

Rexlion · Jun 30, 2019

Try cleaning the contact ring, preferably with something like DeOxIt which prevents oxidation. Not sure, but that might do the trick.

Berneck1 · Jun 30, 2019

I have a D3a and only use Eneloop Pros in it. Never had an issue like this. However, twisty type lights can be a little trick sometimes. Make sure the contacts are nice and clean. Although, the fact that it works fine and then has to be reset sounds like it might be something else.

lightfooted · Jun 30, 2019

Definitely suggest cleaning the contacts and threads. I don't have that model but my own P20 has acted a bit weird a couple of times and cleaning the head contacts solved the issue.

Strintguy · Jul 1, 2019

Send it back if it's under warranty for a replacement?

RobertMM · Jul 2, 2019

Clean it up first, all contact surfaces. Those inside the head and the threads of both the head and the body, then make sure the lip of the body is dry/unlubed when you are done lubing the threads.

I have a D25A Ti and a D3A Ti, they both act funny when they collect some gunk on those especially the ring inside the head that the lip of the body touches when you tighten the head.

Illumination · Jul 5, 2019

Thanks all. I've tried cleaning the head and it doesn't seem to help, but I'll try it again. The biggest challenge I have is that the problem is intermittent; its not easy to replicate and doesn't happen every time. This makes it much tougher to pinpoint the source of the issue.

I've done most of my testing with eneloops (used a bunch of them from different vintages) and have seen the issue with them all. I have not replicated the issue with an Alkaline or 14500 yet but have only been able to do limited testing. As I mentioned in my earlier post the issue happens when I leave the light untouched for a while (seems like at least several hours) so it takes a lot of time to try each new battery.

The dealer has been working with me and offered to send a new head and tail but has not offered to allow a return (even though I pointed this out less than 30 days after I ordered the light). They said my alternative is sending it back to EagTac in China (pretty significant cost). This is a much lower level of service than provided by some other China-based manufacturers like Fenix that handle warranty work in the US through their dealers.

lightfooted · Jul 5, 2019

Illumination said:
Thanks all. I've tried cleaning the head and it doesn't seem to help, but I'll try it again. The biggest challenge I have is that the problem is intermittent; its not easy to replicate and doesn't happen every time. This makes it much tougher to pinpoint the source of the issue.

I've done most of my testing with eneloops (used a bunch of them from different vintages) and have seen the issue with them all. I have not replicated the issue with an Alkaline or 14500 yet but have only been able to do limited testing. As I mentioned in my earlier post the issue happens when I leave the light untouched for a while (seems like at least several hours) so it takes a lot of time to try each new battery.

The dealer has been working with me and offered to send a new head and tail but has not offered to allow a return (even though I pointed this out less than 30 days after I ordered the light). They said my alternative is sending it back to EagTac in China (pretty significant cost). This is a much lower level of service than provided by some other China-based manufacturers like Fenix that handle warranty work in the US through their dealers.

The head is where the electronics are located in the flashlight, so actually yeah...they are offering to replace the whole thing. Are you sure it's not your Eneloops? Sounds like they may be old anyway. As a matter of troubleshooting, after cleaning contacts the next step should always be to try known good power source...or in this case new eneloops since those are your preferred cell. Take the time to do the testing. Otherwise even if you DO manage to get a replacement it could end up doing the same thing.

Power supply has been the source of more of the issues I've had to deal with than anything else.

ecallahan · Jul 5, 2019

I purchased a D25a with similar issues last winter. If cleaning doesn't help, get the new head from the dealer. Mine was definitely a problem with the controlling unit. New head and no more problems.

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Illumination · Jul 13, 2019

ecallahan said:
I purchased a D25a with similar issues last winter. If cleaning doesn't help, get the new head from the dealer. Mine was definitely a problem with the controlling unit. New head and no more problems.

Sent from my iPad using Tapatalk

Thanks! Nice to know I have company.

I knew it wasn't my eneloops when I installed a brand new Duracell... while the problem didn't happen the first time (it never does) I left the light alone and sure enough next time it didn't work...

The dealer is sending me a replacement head, so waiting for that now.

Weird Issue: EagTac D3A + Eneloops

Illumination

Flashlight Enthusiast

Tac Gunner

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Rexlion

Enlightened

Berneck1

Enlightened

lightfooted

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Strintguy

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RobertMM

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Illumination

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lightfooted

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ecallahan

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Illumination

Flashlight Enthusiast

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