Keeping the flashlight steady is one of the most important things while working with tools in dark spaces. Pretty hard to get work done if you can’t see right, after all.
Well, it’s hard to see much at all if your DeWALT 20v flashlight blinks on its own during use. I’ve got a pretty good idea about what’s causing this, so keep on reading to learn more!
4 Methods For Dealing With A DeWALT 20v Flashlight That Blinks
- It’s Supposed To Happen
Even though users may not know this, the blinking is actually an intentional feature on some DeWALT flashlights. It has a purpose and isn’t necessarily something wrong with the light.
Now, as much as I’d like to say that it’s nothing to worry about, that isn’t the case. The light blinks because there’s an issue going on still, but it’s probably not what you thought.
DeWALT flashlights, like the DCL040 model and some others, intentionally blink at times. When they do so, they’re letting the users know that the light was on for too long.
Light produces heat, and any flashlight gets hot after a while. So, to prevent overheating, some DeWALT 20v flashlights start blinking to let users know the temperature is getting too high.
Blinking lights (on models that support this feature) are a sign that you need to stop using it ASAP. So, don’t worry about troubleshooting or anything else like that.
Stop using the light for a while, and it’ll cool down on its own. After that, the next time you use it, it won’t blink the same way. Just remember to take breaks during use so it doesn’t overheat again.
- Low Battery Sign
Other than letting users know about overheating, there’s another intended reason for the blinking light too. That reason is to tell users that their battery needs charging.
Related: Reasons Why DeWALT Battery Not Charging No Light
It’s much less serious than overheating or issues with the light. It’s just a sign that your flashlight is running low on power, and you should take the battery off to charge it.
Once again, there’s no need to worry as long as you can confirm this is an intentional feature with your particular model. A quick search online will answer that for you, though.
Even though it’s annoying to have the light blink when you’re using it, it’s helpful. It’s better to have it blink and give you a sign to wrap up your work, instead of having it just turn off out of nowhere.
Charge the battery until it’s back to full and see if that stops the flashlight from blinking afterward. If it does, you’ll know the feature was just working as it’s meant to!
If your DeWALT battery is experiencing charging problems, I have made a short video which shows how you can fix this. You can watch it below.
You to reset the battery in order to fix this issue. To do this, you need another healthy DeWALT battery with similar specs.
Connect the B+ and the B- terminals of the two batteries. Then, press the battery indicator to make sure it is receiving power. Just jump start it for few seconds and the reset is done.
I also have a video about how you can identify a bad cell inside a DeWALT battery. You can do this if you want to replace a single cell or some cells inside your DeWALT battery.
In order to identify the bad battery cell, open the DeWALT battery cover and set the multimeter to measure DC voltage.
Use the red probe to touch the battery side with red wire and use the black probe to touch the battery side with black wire.
Each battery cell should have an output voltage of 3.6V to 4V. If the measured voltage is less than 3.6V or more than 4V, it means that battery cell is not good anymore.
- Loose Battery Is Causing Flickers
Moving on to actual troubleshooting, I think the biggest reason for a DeWALT flashlight flickering/blinking is likely the battery going loose, ruining the flow of power.
Something like that might happen when the contact points get dirty. Any kind of mess that could get in the battery’s way will stop it from working properly.
Corrosion and debris are the two biggest examples of this. Both are common on metal contact points like the ones on these DeWALT flashlights and batteries.
Look at the contact points (in the image below) on my DeWALT flashlight. They’re notably clean. If something is restricting the battery, you’ll be able to tell and clean it off rather easily.
Use WD-40 or something similar if there’s corrosion. Otherwise, a normal cleaning spray should work just fine and get rid of any gunk on the prongs.
Keep a look out for any bending or other physical issues with the contact points while cleaning. Those kinds of things can cause a loose connection too, and explain why the light is blinking.
- Dying Battery Causing Flickers
I already told you about how low batteries can make DeWALT flashlights blink intentionally. However, something much more serious and not as intentional is a dying battery causing this.
These flashlights are pretty strong, and they need a steady flow of power to keep them lit. Without that, they won’t function right and present issues like blinking.
Dying/weak batteries are something that can cause this exact situation going on with your flashlight. I have a dead battery of my own, which you can see in the photo down here.
Try on another DeWALT battery with the flashlight to see if the same thing happens. I’m certain that it won’t blink anymore after you put on a new, fully charged battery.
If it so happens that I’m right about that, it’ll prove that the battery was to blame. The cells inside are likely running low on voltage, and aren’t strong enough to power the flashlight anymore.
Buying a replacement battery and using that instead is the only way to get your DeWALT 20v flashlight to stop blinking on its own.
But before you buy a new DeWALT 20v battery, you can watch my video below about how I fixed my DeWALT 20v battery that wasn’t fully charging.
In order to fix this, you also need to reset the battery. And just in my previous video above, you also need another DeWALT battery with similar specs.
Connect the B+ and B- terminals of the two batteries. Let them stay connected for around 15 seconds.
Then, put the battery to charge again on the charger. It should now be able to fully charge up to 3 bars.
