LED Flashlight issue.

I have a problem with some LED flashlights. I carry one on my belt.

When garage door openers started using circuit boards instead of relays, you could wet your finger, touch the push-button contacts and it would run. Also after a time the limits would not shut it off and had to be cleaned. I was told that due to the low current, there was no arcing to keep the terminals clean.

As this relates to LED flashlights, I am finding that after a while my LED flashlight stops working. I change the batteries. After having this happen quite frequently, I thought it was "eating" batteries. Eventually I inadvertently discovered that if you merely take the batteries out and put them back in, the light works fine.

The problem is, what if you suddenly need the light in an important situation and even with good batteries, it won?t light. I supposes I could rotate batteries in my LED flashlight every day but, what about the two or three laying around the house/camper.

Has anyone else experienced this?

Battery terminals in the device and the battery terminals on the actual battery(s) will oxidize over time.  A good method for cleaning them, and restoring the "workability" of the light is to use a pencil eraser to clean all the terminals....both the battery terminals and the device terminals.  Cheap and inexpensive and works great.

After cleaning the batteries and the contacts, keep your fingers off of those surfaces.

I've had that experience, most commonly with little $1.99 models form Harbor Freight, KMart, etc.  Like you, I've learned that if it suddenly doesn't work, remove and re-insert the batteries and there is a solid chance of success.    The somewhat larger and more expensive models using the Cree high-intensity Leds don't seem to have that problem. Not sure if its the higher current draw or simply better quality components.  Those I can leave in the trunk of the car for several months and be fully confident they will light when needed.

lynnmor said:

After cleaning the batteries and the contacts, keep your fingers off of those surfaces.

Click to expand...

)  I agree!

Dick Zeiter said:

you could wet your finger, touch the push-button contacts and it would run

Click to expand...

I had to laugh when I read this as it brought me back to my early days in camera repair when flashbulbs were in use. I repaired 1000's of flash guns with corrosion damage from the owner licking the flashbulb before inserting it for better conductivity. Probably worked the first couple times until the corrosion set in. Of course the customers almost never would admit to it. I couldn't even break my Mother from the practice.

Now if this is your practice with the batteries...

Tom

What about using a dab of dielectric grease? Could that reduce the problem?

P.S. I was not licking the batteries. That was merely an example that applied only to newer garage door openers when circuit boards first started to be used instead of relays.

I carry a cell phone everywhere I go and all modern cell phones have a built in flashlight mode. No need to carry one.

try looking around the neighborhood for your lost cat with cell phone light. It's great within it's limitations, but not a replacement for a good flashlight outside.

kdbgoat said:

try looking around the neighborhood for your lost cat with cell phone light. It's great within it's limitations, but not a replacement for a good flashlight outside.

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I am not dumb enough to let my cat outside. Strictly inside. I haven't had a job for my cell phone flashlight that it has failed at yet.

I take my cheapo led lights apart, clean the three batteries and terminals with rubbing alcohol and a q-tip. 

Keep fingers off the contacts....

Good for several months. 

Tom, I never suggested that you were dumb. I was just pointing out an example of when a cell phone light is not the right tool for the job. Lighten up. By the way, there is always the possibility that one of your cats can get outside. I know, yours NEVER will.

kdbgoat said:

Tom, I never suggested that you were dumb. I was just pointing out an example of when a cell phone light is not the right tool for the job. Lighten up. By the way, there is always the possibility that one of your cats can get outside. I know, yours NEVER will.

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I did not think you thought I was dumb. I have had a cat escape three times in 8 years. Yes they will escape, it is their job.

Our cat occasionally escapes out the patio door and immediately goes to the front door and cries to come back in!

Not only do I use the light on my phone A LOT....I also take pic's of the hard to see/read things. Then just zoom in on the pic.

I also use my camera on low light setting with flashlight on. The eyes of a cat almost glow on the camera.

I have also discovered the best way to keep a from escaping.......Don't have a cat...LOL

Dick Zeiter said:

I have a problem with some LED flashlights. I carry one on my belt.
As this relates to LED flashlights, I am finding that after a while my LED flashlight stops working. I change the batteries. After having this happen quite frequently, I thought it was "eating" batteries. Eventually I inadvertently discovered that if you merely take the batteries out and put them back in, the light works fine.
The problem is, what if you suddenly need the light in an important situation and even with good batteries, it won?t light. I supposes I could rotate batteries in my LED flashlight every day but, what about the two or three laying around the house/camper.
Has anyone else experienced this?

Click to expand...

Dick Zeiter
A of dab dielectric grease on each end of each battery before you put them in will solve that problem.
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