My DeWalt impact wrench comes with a 20V battery and I know batteries not charging all the way usually signals some serious problems.
If you noticed your DeWalt 20V battery only charges to TWO bars, you should deal with that as soon as possible.
This normally when you press the battery indicator, the third indicator LED won’t light up no matter how long you charge it as shown in the video below:
I’m here to help you do that by walking you through some solutions that I tested out when my own battery was going through similar problems!
Before that, you might want to check the voltage of your battery as shown in the video below to make sure it is an healthy battery.
Related: Interchange DeWalt battery with Black & Decker Battery, is it possible?
DeWALT 20V Battery Only Charges Up To Two Bars
- Battery Age
Batteries get worse with age as you drain and recharge them over and over.
If your battery is old, it’s capacity will be less than what it was when you first got it.
Just take a look at my battery too. It was made in 2021, and isn’t as strong as it once was.
Sometimes I found that the weak battery won’t allow my impact wrench to remove the lug nuts smoothly as they are normally more tight.
This is due to the DeWalt impact wrench is not strong enough with weak battery.
I’ve noticed that it drains quicker, charges a bit slower and even not charging at all.
If yours is even older, that’s the reason your battery doesn’t fully charge anymore.
Before that, I would suggest you to try to jump start the battery to reset it as shown in the video below.
Sometimes this simple trick will the issue.
- Faulty Individual Battery
This one is a bit more complicated, so I took the cover off my DeWalt battery to show you what I mean.
Read: DeWALT 20v Flashlight Blinks: Solutions I Recommend
As you can see on the left, there are five individual batteries on the top, and another five battery cell at the bottom.
I believe these individual batteries are connected to output the 18V to 20V overall voltage.
All of these are connected to each other and power the battery. If even a single one goes bad, that’ll worsen the overall performance of the battery.
It might cause the tool that this battery connected to receive no power.
My video below will show you how to identify the bad battery cell, the normal cell will output voltage of 3.6V to 4V.
Sometimes it might even cause the entire impact wrench not able to turn and spin normally.
Make sure that there’s nothing wrong with the individual batteries on your DeWalt.
I recommend checking each ones voltage, and getting any bad batteries replaced.
- Charger Faulty and Incorrect Charger Voltage
I don’t think it’s fair to blame only the battery.
Personally, I’ve seen issues with the charger every now and then too. You could be facing those right now.
Confirm that your charger isn’t faulty or too old to handle the workload anymore.
Try using a multimeter to confirm it’s getting the right amount of voltage.
Read: What To Do if DeWalt 20V Charger Is Not Working
Speaking of voltage, you can see in the image above that my charger output specific voltage specifications.
My charger output 22 VDC, make sure you only use this charger to charge compatible battery.
For example, you should not use the charger above to charge the 12V DeWalt battery, as this charger might not compatible with it!
Verify that your battery is suitable for the charger, otherwise it could cause serious long-term problems for the device, or even safety hazard for yourself.
- Charger Temperature Issue
Note the highlighted sticker on my battery charger.
You can see how it mentions the recommended temperature range for my battery charger, which is between 4°C to 40°C.
I believe your DeWalt charger will have information like this too on it.
What I’m going to say next is pretty obvious. Just ensure that your charger and battery stay within this temperature limit.
Otherwise, when the battery gets charged to too hot or cold, it would trigger the Hot Cold Delay and the DeWalt charger indicator would flashing fast.
Read: All meaning of light on the DeWALT Charger
Your battery shouldn’t overheat or get too cold if you just keep it in room temperature.
If it’s still overheating despite that, there might be a short you need to get checked out.
Read: DeWalt battery indicator and charger indicator not working
- The Third Battery Indicator LED is Faulty
One more thing I can think of is that your battery might actually be charging the whole way, but you think it’s not because the battery indicator LEDs are faulty.
I can speak from experience that the impact wrench light burning after regular use isn’t that surprising.
Let me give you a closer look at what these indicator LEDs look like by showing the ones on my battery.
If there’s any visible damage on the LEDs, that’s the reason they’re not turning on. So, your battery is probably charging fully, but you can’t tell because of the indicator being damage.
Conclusion
I hope everything I’ve shared here today can make sure your DeWalt battery charges from only two bars to all three bars!
This is a common enough problem for people with older batteries, but I’m sure you should be able to figure out what’s wrong with the tips above.
