BASIC FLASHLIGHT TROUBLESHOOTING GUIDE

Bullzeyebill

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Bringing this to the top. Good thread and deserves to be a sticky, what with all of the threads started about "my broken light".

Bill
 

Newuser01

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I have found that some lights , pills, or the switch assembly becomes loose (some times even new out of box) that tightening it can eliminate problems such as whining and/or won't turn on.

This issue can and do effect premium lights as well as cheap ones.

Regards.
 

gravelmonkey

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I see too many threads about "my light won't come on" where people just do not know the basics of what to do in that type of situation, so here it is in a nutshell:

BASIC FLASHLIGHT TROUBLESHOOTING PROCEDURE:

1 – Check the battery polarity (most often positive towards the head, but not always)

2 - Make sure all parts are screwed in all the way and remove / reinstall your dropin if applicable while inspecting for broken parts.

3 - Try a new non-rechargeable battery (and new bulb if it’s an incandescent)

4 - Clean all contacts: inside the head, spring(s), tube ends and threads. (Rubbing alcohol and a Q-tip work fine or this)
4A - For twisties and lights that have erratic behavior: check if your o-rings are not creating too much friction (too dry or too big) or not enough tension (too small). Big o-rings can prevent contact, small o-rings can make contacts happen when not desired, causing flickers or undesired mode changes.

5 - Remove the tailcap and short the end of the battery with the end of the tube (a trombone works just fine).
5A - If this works: tighten the tailcap retainer ring (note that some are reverse threaded).
5B - If tightening the retainer ring doesn't work dismantle the switch, clean all contacts inside the switch area
and reassemble.
5C - If this does not fix the problem, but the light comes on when you short the battery and the tube end, you most likely have a defective switch.

6 - Contact you dealer. If the dealer warranty is over, contact the manufacturer. Some dealers and manufacturers will honor the warranty for longer than stated or will provide replacement parts for a reasonable fee and sometimes even for free.

Don’t just give up on a light or brand just because your light didn’t come on.

As a standard maintenance procedure, you should lubricate your o-rings (see the comprehensive grease and lube thread for more details) and clean your contacts on a regular basis (at the very least once or twice a year up to once a month, depending on your usage.) Once a year, I check that my retainer rings are screwed in properly and I basically never have any problems.

Let me know if I forgot anything and I invite you to share your tips & trick or stories of a light that neede a simple maintenance to get going again :thumbsup:

Trombone?!?!

I laughed out loud and now everyone on the bus thinks Im insane....
 

Cataract

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:ohgeez: Emmm... yea, that would be a paper clip... don't know how that one got through LOL. Although, any musical brass instrument should conduct enough to let the current through, but you might find the tuba a little tough to handle while playing with a flashlight (on any other forum this would have been said the other way around)... and you might want to think twice before putting your lips to something that has a couple of amps going through - and I don't mean guitar amp here (some people might thank you for not playing the trombone on an amplifier, though).

I corrected the original post to avoid confusion and help prevent flashlights to be blown onto walls or musical instruments to mysteriously start sound like the hamster got stuck in there.

gravelmonkey: I hope you don't see too many of the same people on the bus each day.

fyrstormer: correct, trombone is both the musical instrument and a paper clip in French. Don't know if it was me or the spell-check that got mixed up.
 

One missed call

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Hi there.

Informative thread!

I have a Jetbeam DDR30 which is about 2 months old and has about 3-4 hour of use. The other night I was using it and moments after turning it on, it shut down. This happened two (2) times over a 1 hour period in the same night. The first time I noticed the battery tube/tail cap was not screwed on completely (could be tighten just a bit more). Shortly thereafter, it happened again. Both incidents occurred moments after first turning on the light. The light allows for 'momentary on' by depressing the on button for a short period. After holding the on button for more than 2 seconds, it stays on and the DDR shows an "H" denoting 'high.' In both instances I had depressed the on button for a minimum of 4 seconds and the "H" appeared.

At the time I had Panasonic NCR18650A 3100mAh batteries installed. Despite numerous attempts, I have not been able to get the light to trun off erratically again (good I suppose).

Anyone know what could be the culprit here?

Finally, as for cleaning the contacts, should I need to do that on a factory fresh barely used light?

Many thanks in advance for any help!
 

Cataract

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Hi One Missed Call

You had to get me to check out the Going Gear review! Good thing I put a restriction on my budget, else I might be ordering a DDR30 myself...

Do start with my basic list even on a brand new light or right after doing a good maintenance as this solves over 90% of all problems.

Your first suspect in this case is lube on the threads, tube endings or battery carrier contacts. I always start with cleaning threads and all contacts and seldom have to go any further, even on spankin new lights - when it does happen.

Also, make sure your battery level is not low. You do have a battery level indicator on this light, so check out what it says... 1 = low batteries. When batteries are low on regulated lights, they normally cycle down through the modes and then just turn off.

In your case I'd say also give your battery contacts a swipe as well just in case. This light has a battery carrier, so you also want to make sure all the screws are nice and snug on the carrier as lots of battery carriers use the posts as conductors.

Let us know if you find out anything or if it keeps going and going and going...
 
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One missed call

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Thanks Cataract! I appreciate the thread as well as the response.

I will keep you all posted - I am out with it now. So far no issues.

As for discovering a new light you may want by chance, I am in the same boat. Just when I thought the DDR30 was the highest compact LED light out (ignoring the TM26 which I don't like the look of) I find another - most recently the L3 X40 XML2 U2. Or even more recently, the Lupine Betty - which is a bit above my pay grade. :)
 
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Cataract

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You're very welcome... and you still haven't seen nothing yet ;)

CPF can point you towards the wallet blackhole of flashlight addiction :devil:
 

One missed call

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You're very welcome... and you still haven't seen nothing yet ;)

CPF can point you towards the wallet blackhole of flashlight addiction :devil:

I am beginning to see that! I haven't been here long but have a persistent itch to add to my collection and visit CPF a bunch of times in any given day. I am barely 4 months in and now have purchased 5 lights (all of which are between $180 and $300).

I am starting to think CPF should have devote a section of the forum to 'getting help with your flashlight addiction.' :) jk

Budgeting aside, I am trying to do more research for each light I want as it seems that not long after picking one, I always find another I wanted more.
 

Cataract

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I found that spending less sorta happens after finding out the hard way what works best for you, then you aim at more specific interfaces, emitter colors, etc. The temptation level is still the same, but you look at less options, so end up buying a little less.

It sounds like a good idea to have a section to help with our addiction, but it would be like asking an alcoholic how he keeps of booze: he doesn't, but he finds different bars to get drunk at (in other words, you'd be pointed to different dealers, manufacturers or places to play with your lights.)


To help anyone looking for a problem resolution in this thread:

I exchanged a few PM's with One Missed Call and it would seem there was some grease on his light's tube endings. This can happen when the guys doing the final assembly put too much lube or just have some lube on their hands or whatever - I've done it myself a couple of times. The light works fine so far and I bet it will keep rockin'.
 

One missed call

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I found that spending less sorta happens after finding out the hard way what works best for you, then you aim at more specific interfaces, emitter colors, etc. The temptation level is still the same, but you look at less options, so end up buying a little less.

It sounds like a good idea to have a section to help with our addiction, but it would be like asking an alcoholic how he keeps of booze: he doesn't, but he finds different bars to get drunk at (in other words, you'd be pointed to different dealers, manufacturers or places to play with your lights.)


To help anyone looking for a problem resolution in this thread:

I exchanged a few PM's with One Missed Call and it would seem there was some grease on his light's tube endings. This can happen when the guys doing the final assembly put too much lube or just have some lube on their hands or whatever - I've done it myself a couple of times. The light works fine so far and I bet it will keep rockin'.

Just an update for those of you who are interested. As Cataract notes above, the issue seemed to have been resolved, but in reality it was not.

It's been a week and I think (with help from Cataract), I may have isolated the issue. The Panasonic NCR18650A batteries which I had been using (~69.4mm in length), were a VERY tight fit (In fact, I ripped a small part of the shrink wrap near the top of one of the cells as I pulled it out). Although I managed to get the batteries into the carriers, the excess(ive) compression may have caused either a battery or the battery carrier not to function properly.

I am now using Eagletac batteries which are shorter, and so far, so good.

Thanks Cataract!
 
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Cataract

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My pleasure. If you had to almost rip the battery out it definitely wasn't a good fit.

It is worth mentioning that protected Li-ion batteries do not all measure the same, often because of the protection circuit but also because of difference in capacities, and that is also a cause for malfunction in some cases. The difference of fit between flat top and button top can also cause contact issues.
 

ken-o

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I highly recommend DeoxIT. I work with electronics all day and much of it is repair work. We have tried all types of contact cleaners and DeoxIT works wonders and keeps the contacts looking good for a long time. Grab a bottle and it will last you a long time if all you are doing is cleaning your light contacts once in a while. I just cleaned my Quark 123 contacts with it the other day and they look as good as new now.

LPS Contact cleaner or denatured alcohol will work fine..
 

Cataract

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A lot of companies building electronic boards and repair companies actually use 70% rubbing alcohol on contacts and even entire boards. Works just fine since it evaporates in a few seconds. I use that all the time and never had a single problem aside needing something stronger to clean real bad oxydation or oily products. Not good for plastics and rubber though, as it dries those up and leave dark plastic finishes looking whitish.
 

Nomad

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I wanted to say thank you for this posting! As soon as I get into a real apartment and unpack, I have got to try going through the list and try to fix my son's flashlight. He is tough on lights...he's 4. :)
 

Cataract

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Thanks. I remember playing with my dad's flashlight like crazy when I was 4, so I really hope you can fix it ;)
 
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