Dewalt battery with low battery symbol

Dewalt Battery Not Charging (6 Easy Fixes! – Updated)

If you are having trouble with your Dewalt battery not charging, don’t worry you’re not alone. 

As with all batteries, Dewalt batteries often go through issues that do not allow them to charge properly. Lucky for you, there are 6 simple things to try before you go out and get a new battery. 

Dewalt Battery Not Charging

Make sure outlet you are using is working

If your Dewalt battery isn’t charging, the easy fix is to ensure the charger’s plugged into a functioning outlet. Plug a different device into the outlet and make sure it works. If the outlet’s defective, try a different outlet and see if charger lights come on when battery is plugged in. 

This sounds incredibly simple, but often times it can be the case. It could be that a fuse was blown or the outlet is damaged. Do not overlook this step, it can save some time and effort.

If the outlet is not working, it will not provide power to the charger, and therefore, the battery will be unable to charge. So check the outlet by plugging in another device such as a phone charger to ensure you are getting power.

So you determined the outlet you are using does in fact work, however, the battery is still not charging. Luckily, we have other ways to fix the problem: 

Make sure the charger is working: Try another battery

While the charger is plugged in, try a different Dewalt battery. This will quickly determine if the problems with the particular battery or if the charger is not working. 

When you plug in a different battery, if the lights on the charger appear, this tells you that the charger is working. So now you know the issue is with the battery. 

If using a different battery and you still don’t get indicator lights on the charger, this means the charger is the issue. It is rare but you also could have two faulty batteries. 

If the issue is with the charger, I recommend you reach out to Dewalt as most equipment comes with a 3 year warranty. 

You determined that it is indeed an issue with the battery and not the charger, then continue on to the next fix. 

Press the button on the battery when plugging in

You must press the button on the battery, as it slides down the charger. This ensures there’s an appropriate connection between the battery and charger terminals. You will still get a solid red light on the charger if this is done incorrectly, however, the battery isn’t charging. 

Yellow battery on front of Dewalt battery to press when putting battery on charger

As seen in the picture, there is a yellow button on the battery (color will vary depending on battery type). This is the same button you press to remove the battery from a tool. It is essential that you press this button when sliding the battery down the charger. If it is done right, you should hear an audible click, this will indicate that the battery is on properly. 

If this is not done properly, then the battery will just be resting on the charger. When this happens it will give the appearance that the battery is fully charged. There will be a solid red light showing on the charger (just as appears when it is indeed fully charged). 

What happens in this scenario is that you think the battery is fully charged, so you go and use it, but it only lasts a couple minutes. This is a quick indication that the battery has not been properly placed on the charger. 

Just a reminder, if the battery is not fully charged, you should see a blinking red light on the charger when the battery is plugged in. 

Below is a guide to the charging lights that you will see on a Dewalt charger: 

Description of what indicator lights mean on Dewalt battery charger

If you are getting an audible click when placing the battery on the charger, and you find the battery is still not charging, don’t panic. We have a few more fixes to try. 

Clean the connections of dirt and debris

If there is dirt on the terminals of the battery and or charger, this will not allow for a good connection. This interruption in the connection will not allow the battery to charge. 

Charging terminals on Dewalt battery
Battery terminals
Charging terminals on Dewalt charger
Charger terminals

The terminals seen above, on both the battery and charger must be clean and free of debris in order to maintain a solid connection. 

Often the debris will be visible (dust, corrosion, dirt, etc). However sometimes they may appear clean but in fact there is enough “gunk” in there to disrupt the connection. 

It is important, if the terminals appear clean and nothing is standing out, “STILL DO NOT SKIP THIS STEP”. There is absolutely no harm in cleaning out the terminals and it may solve the issue. 

The terminals on the charger are bigger, and in my experience much easier to clean. I use a Q-tip and some rubbing alcohol. You want to make sure you hit both sides of the terminal with the Q-tip.

Using a Q-tip to clean the terminals on a Dewalt charger

The terminals on the battery are much smaller and harder to get into. For this I have found either an envelope or sand paper folded over does the trick. You want to use something that will be firm enough to not crinkle or loose its shape when you slide it in the slits. I have also found you can dip the sandpaper or envelope in rubbing alcohol to enhance the clean. 

Using an envelope to clean the terminals on a Dewalt battery

Often if using a white material you will actually see the black soot coming off as you stick it in the slits. 

Once you have cleaned all the terminals (on the charger and battery), try plugging the battery back in. You should see a blinking red light on the charger, if the battery is charging.

This is a quick and easy fix that is good to get in the habit of doing every couple of months. No matter where you store the battery/charger, debris will build up. It is important to keep the ports clean in order to maintain a quality connection. 

Slowly charge the battery for 2-3 minutes at a time

If a battery gets below a certain voltage, it can become flat. If that is the case, you can try charging the battery for 2-3 minutes at a time for a total of about 30 minutes. You can think of this as a way to jump start your battery. 

Graph showing how battery can enter sleep mode if used beyond a certain battery charge level.

Think of a flat battery as being fully dead. When this happens it cannot hold a charge so by putting it on the charger for shorter bursts will help kick start it back to life. Usually after about 30 minutes of these short bursts, the battery will have enough juice that it can now be fully charged. Again a blinking red light on the charger will indicate if this fixed the issue.

If these 5 fixes have not worked to get your Dewalt battery charging, there is one final thing you can try before contacting Dewalt. 

Use speaker wire to connect dead battery to a healthy battery

If you have tried all the other steps and the battery will still not charge. Then you can try and kick start the battery with some speaker wire. 

In older Dewalt batteries (that do not have an indicator light) it can be difficult to determine if a battery is fully dead. The best indicator is if you put the battery on a tool and you get absolutely no power. With newer Dewalt batteries that have the indicator light on the front. You can determine a battery is dead if you press the indicator button and no lights come on. 

Dewalt battery indicator button and lights.

In this case a couple things may have happened. As described above, the battery may have gone flat. Or the battery was so depleted that it went into sleep mode. If this happens, the battery will not even register when placed on the charger. So we need to give it a jump start, just like a dead car battery. 

In order to perform this technique, you need to have a fully functioning and charged Dewalt battery. 

It is important to note, that on every Dewalt battery there is a positive side labeled “B+”, and a negative side labeled “B-“.

Dewalt battery negative terminal (B-) and positive terminal (B+).

Place the two batteries next to each other. Take some speaker wire with the covering removed at the ends so the wire is exposed. Connect the “positive” terminal on the healthy battery to the “positive” terminal on the dead battery (B+ terminal). Then take a another piece of wire and connect the “negative” terminal on the healthy battery to the “negative” terminal on the dead battery (B- terminal). Make sure that you stick the exposed wire deep in the terminal so it maintains contact with the metal. 

Using speaker to connect the positive (B+) terminal on a dead Dewalt battery to a fully charged battery

Hold the wires in place for 5-10 seconds. That should provide enough “juice” from the healthy battery to jump start the dead battery. Then disconnect the wires. Now try placing the dead battery on the charger. It should indicate that a charge is in progress (flashing red light). 

Holding speaker wire in place to jump start dead Dewalt battery with a full charged battery. Connect the positive to positive (B+) and negative to negative (B-).

Here is a video on how to use speaker wire to jump start a Dewalt battery:

Conclusion

There are a number of different reasons why your Dewalt battery may not be charging. Luckily, you can try these 6 proven fixes to get the battery charged again: 

  • Make sure outlet you are using is working
  • Make sure the charger is working
  • Ensure you are putting the battery on the charger properly
  • Clean the battery and charger terminals of dirt and debri
  • Slowly charge the battery for 2-3 minutes at a time
  • Jump start the dead battery using speaker wire and healthy battery

If you have tried all of these fixes and the battery is still not charging, you should go ahead and contact Dewalt at: 1-800-433-9258. 

It is also good to know, most Dewalt products come with a 3 year warranty. You can look up more info on Dewalts warranty policy for further information. 

Were you able to get your Dewalt battery charged again? If so, let me know in the comments section.

17 comments / Add your comment below

  1. Thanks David, great guide! The “Use speaker wire to connect dead battery to a healthy battery” section saved me a long lost battery that I found and I was about to trash! Never would have thought to try that.

  2. I bought 2 Dewalt batteries on EBAY. One charged right away, the other seemed dead: no lights of any kind on the charger. I jumped it just like you show, and now it’s charging like it should. Thanks,.

  3. My battery was reading 3.4v but the charger wouldnt respond to it. Jump start technique worked. Could probably jump it with a 9v alkaline or a 12v Dc adapter also if you don’t have another 12-20v tool battery available. Anything to break it out of sleep mode.

  4. I bought the old type ni-cad De Walt drill a long time ago now (before lithium). I injured my back never got to initially give the DeWalt it’s first charge it never got used for 12 months so it went dead flat and never took a charge. They (ni-cad) were the pole type batteries would it be advisable to kick start that ni-cad with a lithium battery going b+ to b+ and the b- to b- on the ni-cad terminals🤔…thanks.

  5. Hi David, my TWO 36 volt LI-ION 2.0 AH BATTERIES WONT CHARGE. Neither of them have any charge so I can’t connect the wires to boost the other one. I have 18 volt 5.0 ah batteries so have tried connecting to one of them but this doesn’t work. Obviously I am assuming that the b+ and b- connectors are the same on both batteries (hope this makes sense). Any other advice as to how to get them to charge?

    1. Have you tried doing the short quick 30 second charges for 10-15 minutes? Try and wake one of them up so you can then jump the other.

  6. Hi David S, this all looks helpful although my starting point is that with one of the large DW XR Flex batteries, when I put it into the yellow fast charger (that I’ve always used with it) it seems to be okay for about two minutes (fan is on, seems to be running normally) then it just stops dead. If I try again the same thing happens. Have you experienced anything like this? I’m unsure whether the charger or battery is at fault. The battery has had only light use in the house as a bumper phone charger so things like heavy daily use or workshop dust/sawdust aren’t factors. Any thoughts on this would be great, thanks!

    1. Could be the charger so try another battery on there. Also the battery could be in that dead zone that I described above. Try doing those short burst 30 second charges for 10-15 minutes to try and wake it up. Also could try the jump start method with another battery.

  7. My 6 ah flex volt turns red real quick then black. It shows two battery icons on battery but stays lit then slowly fades . But battery still has charge. Just won’t take any charge. I tried all methods

  8. Hi David my 20 volt max battery won’t charge red lite just blinks. Have left batteries in charger all night still no charge.

  9. You just saved me a lot of frustration and expense, thank you! I’ve had a dead 9AH battery from a chain saw I bought two years ago that wouldn’t charge and I was about to take it for recycling and buy another. Two pieces of wire and 10 seconds later it’s alive and well.

  10. Jump starting it actually worked, I had a brand new power stack that id used once and it wouldn’t even register on the charger, was about to exchange it for a new one until I saw your post.

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