7 Common DeWalt 20V Trimmer Problems

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By Arthur Mbanefo

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Many of you need help understanding when we talk about dewalt 20v trimmer problems. We are relating to mechanical issues that are predominant with this machine. These are almost inescapable issues. 

And 8 out of 10 DeWalt 20v owners will encounter these problems. 

But don’t worry! Before you click away, I will tell you what they are and whether there is a simple fix.

DeWalt 20V Trimmer Problems

DeWalt is a renowned company that leads in battery tools, and its Trimmer aims to impress its owners.

Its efficiency is no doubt a significant concern amongst mower enthusiasts. It has a robust gear-drive transmission that powers it when in use.

However, despite DeWalt’s reputation for reliable tools and appliances, some customers have reported problems with this device.

Keep reading as we analyze them one after the other.

1. Trimmer Won’t Start

Just imagine how frustrating it will be to pick up your trimmer to work and it doesn’t start. I get it.

A whole lot of problems could be the cause; fortunately, most times, it’s easy to fix.

The leading cause of these problems are; dead batteries, bad chargers, poor connections, and dirty vents.

However, that should be your first concern since a battery powers the trimmer. Because the moment things go wrong with the battery, nothing else works.

Therefore, always test if the battery is charged using them on other tools, and charge them if they have low voltage.

Also, you need to inspect any form of leak in the battery. A reduction in the amount of acid could cause the battery to malfunction.

Note this: you must avoid running down your Trimmer’s battery, which could cause total damage.

2. Trimmer Turns Off When In Use

Nothing could be more frustrating than working in the garden and the trimmer suddenly turning off.

However, if the trimmer is suddenly off, it could be due to a few issues. One possibility is that the battery is low and needs to be recharged.

Another possibility is that the trimmer head is jammed with grass or debris, which can cause the motor to overheat and shut off.

Finally, there may be an issue with the trimmer’s motor or wiring that is causing it to shut off unexpectedly.

3. Battery Does Not Charge

We all know that a battery powers the Trimmer. Therefore, it is regarded as the heart of the trimmer.

So, if the battery is not charged, it is as good as useless.

Therefore, if the battery fails to charge, it may be due to a faulty charger, a damaged battery, or an issue with the electrical outlet that the charger is plugged into.

To solve this problem, try using a different outlet, checking the charger’s connections, and inspecting the battery for any damage.

If none of these solutions work, it may be necessary to replace the battery or the charger immediately.

4. Trimmer Not Performing At Capacity

The DeWalt trimmer usually spins a 0.095 inches line up to 5800 RPM at its maximum setting. This makes it possible to glide through edges easily.

However, if it performs below this, it could be due to a few different factors.

The trimmer line may be worn or damaged and needs to be replaced.  Another issue is that the trimmer head is clogged with debris and needs to be cleaned.

Additionally, there may be an issue with the trimmer’s motor or wiring that is causing it to run slowly. In this case, taking the trimmer to a professional for repair may be necessary.

5. Trimmer Vibrates

One primary reason for owning a DeWalt trimmer is to get a perfect cut while working. And a steady hand can help you achieve that.

Vibrations with your trimmer could reduce the overall efficiency, making it challenging to work with it. However, it is one of the most manageable problems to identify and fix.

However, if your DeWalt 20V trimmer is vibrating excessively, it could be due to a few different reasons.

One possible cause could be an unbalanced cutting head. Ensure the cutting head is securely attached to the trimmer and the blades are not bent or damaged.

Another possible cause could be a worn or damaged cutting line. The moment you realize this issue, you need to replace it.

6. Jammed Up Cutting Line

This is one of the common problems associated with the DeWalt trimmer. Most often than not, it usually occurs when the cutting line is too short and gets stuck in the spool.

However, there could be other reasons for this to occur.

One possible cause is a tangled cutting line. Please ensure the cutting line is wound adequately onto the spool and not twisted or tangled.

Another reason could be obstructing the cutting head, such as debris or thick vegetation. Clear any obstructions and try again.

7. Trimmer Overheating

Just like every other machine, the DeWalt 20V trimmer also produces heat. And a lot of reasons could be the culprit.

Using the trimmer for an extended time without taking a break could make it overheat. Allow the trimmer to cool down before continuing.

Another possible cause could be using the wrong type of cutting line. Ensure the cutting line is the correct size and type for your trimmer.

Finally, it could be due to a malfunctioning motor. Contact the manufacturer or a qualified repair technician for assistance.

Frequently Asked Questions

How Can I Maintain Dewalt 20v Trimmer Maintenance?

Most DeWalt 20v trimmers owners need to maintain their DeWalt regularly. Regular maintenance is essential to prevent frequent Dewalt 20v trimmer problems.

Regularly checking the cooling fins and cleaning them helps you prevent clogging.

Also, always check for any damage to the cooling fins and replace them immediately to avoid overheating and engine damage.

In addition,  check all the electrical connections and clean them to prevent damage and power flow problems.

Lastly, apply adequate grease to the gears to prevent them from burning out and wearing out quickly. Failure to maintain them, you start facing problems upon problems in your DeWalt 20v trimmers.

Why Did My DeWalt 20v Trimmers Stop working?

If your DeWalt 20v trimmer stopped and refused to start or didn’t start, primarily if it has not been used for a while.

You may have a drained battery. Plug your Dewalt 20v trimmer into your charger and see if anything happens.

In most cases, the battery is expected to come up. If the reverse happens, then you need to replace the battery.

What Can I Do To Improve The Run-Time Of My DeWalt 20v Trimmer Battery?

If no permanent damage has been done to your dewalt 20v trimmer battery, you can increase its run time.

The correct procedure for charging your Dewalt 20v trimmer batteries are:

  • Discharge the battery under regular use. Afterward, you remove the battery once you feel a loss of power from the tool.
  • Then, keep the battery out of the charger for at least 2 hours until the battery is at room temperature.
  • Place your battery in the charger. You can do this overnight for a full charge on each cell (At least 8 hours a room temperature).
  • Ultimately, if you notice another difference in run-time, your battery is permanently damaged, or has reached the end of its used life, replace it immediately.

Is It Proper To Leave Dewalt 20V Battery On Charger?

The question should be Does it hurt DEWALT batteries to leave them in the charger?

No! The DeWalt chargers have a maintenance mode that allows batteries to remain in the charger.

It can maintain your battery until you, the user, is ready to work.


The DeWalt 20v trimmer problems can be a real headache for owners of this reliable machine.

However, with proper maintenance, you can help prevent or address these issues before they become significant problems.

Whether changing your cutting line or inspecting the battery, taking proactive steps can help you avoid total damage.

So if you’re a proud owner of this device, don’t let these problems get you down.

Take action today and stay ahead of the game.