DeWalt Electric Mower (Cordless Model) Won’t Start: 12 Possible Causes

An electric mower has numerous advantages over a gas-powered one, including lower noise levels, less effort required to operate, and no fluids to maintain. When they won’t turn on, though, they can be just as aggravating as a gas-powered mower.

Dead battery, faulty battery connection, faulty safety switch, loose or pinched wire, and debris under the mower deck are all reasons why a DeWalt electric mower won’t turn on.

Be aware that if your mower is still under warranty with DeWalt, you should contact DeWalt before attempting any repairs. I’ve provided their email and phone number down here.

Before diagnosing, repairing, or operating, be sure you’ve read and understood all of the safety recommendations in the equipment’s operator’s manual.If you are unsure about how to proceed or if you lack the necessary expertise or experience, you should seek the assistance of a professional.

The Most Common Reasons Why Your DeWalt Electric Lawn Mower Won’t Start

Low Battery Voltage

You are well aware that your electric mower will not function without a proper power supply. A defective battery, link, or charger could be at blame.

Incorrectly Installed Battery

Verify that the battery is placed properly and that the cover is locked shut. Lift the cover on the battery compartment to access the battery.

To install a battery, simply slide it into place until you hear a click. The button used to remove the batteries has snapped into place, producing the audible click.

To charge the batteries, which are sold separately, DeWalt sells electric mowers. Never try to charge a battery with a charger or cord that wasn’t made for that particular battery.

Some things to look into are:

  • The plug where you should make sure your battery charger is plugged in. A regular 120-volt wall outlet must be used.
  • Verify that there is enough juice in the plug.
  • Sun Joe cords have specific plug types that must be used with specific wall outlets. Do not try to alter the plug in any way. A plug with three prongs can only be used in an outlet with the same number of prongs.

Substitute a broken charger or cord.

The Battery Is Overheating

If your mower’s battery becomes too hot, it will shut off and refuse to start. Remove any debris from the mower’s vents. Wait until the battery has cooled down to try starting again.

Scrub the ducts. Avoid exposing the battery or charger to high temperatures.

Dead Battery

A charge indicator is included into some DeWalt batteries. In order to check the battery life of others, they must be placed on the charger.

System LEDThe majority of modern battery chargers feature an LED light that illuminates when the battery is fully charged. For several DeWalt battery chargers, I have included a description of the lighting system.

For information on the meaning of the lights on your charger, consult the manual that came with your unit.

  • A red light indicates that the battery is being charged.
  • If the red light doesn’t blink, charge the battery.
  • Too hot or too cold battery indicated by blinking red light and steady yellow light. Once the battery has reached the optimal charging temperature, the yellow light will turn off. Battery charging speed will be reduced.

Warning Signs of a Dying Battery

When batteries get old, get too hot, or start to fail mechanically, failure sets in. Here are several warning signs that your battery is dying and you should replace it:

  • The battery’s ability to retain a charge has diminished.
  • The battery overheats quickly.
  • It’s taking a while to charge the battery. It takes longer to charge a battery from cold.
  • The charger is now ineffective in recharging the battery. There is either no charge indicator light at all, or it blinks in some kind of incorrect pattern. This can be a false charge.

Displaced Handle

If the handle is not properly positioned, safety switches will prohibit the DeWalt lawn mower from starting. The detachable handle must be opened and locked into the extended position before it may be used.

The handle’s side rails need to be stretched as far as they’ll go. Clamps used to keep the side rails in place should be fastened in place.

The lawn mower may refuse to start if the side rails shift out of place.

If this happens, unbolt the clamps, make sure the handle is fully extended, then rebolt them.

Incorrect Method of Getting Started

If you’ve never used an electric lawn mower before, or if you just got a new one, it’s important to familiarize yourself with the handbook so you can use it safely.

The safety button on your DeWalt tool is designed to prevent accidental starting of your mower by little children who may grab the handle. If you don’t do it exactly like that, your mower won’t start.

Here’s how to fire up your DeWalt push mower:

  • When the battery is properly installed, the safety switch should be activated.
  • Pull the safety bar until it reaches the handle while holding down the safety button.
  • Turn off the security switch.
  • When the safety switch is released, the mower will turn off.

Defective safety switch

Your mower might not start if any of the safety switches don’t work. Each switch can be tested independently by connecting a jumper wire across it.

Just switch out the bad one. Never use your mower if any of the safety switches are broken; doing so puts everyone in danger.

Push Mower DeWalt

  • Make use of the collapsible grip
  • For optimal side rail extension, flip this switch.
  • The safety bar’s toggle switch. The mower is activated by drawing the bar into the handle. Mowers include an automatic shutoff feature when the handle is released.
  • Selector for the emergency stop

DeWalt Lawnmower Wires Come Loose or Get Pinched

Your lawnmower is connected to a variety of electrical outlets via a web of cables. Some of these wires could become loose or pinched, causing a short.

Check for a short by jiggling the wires. Finding a short can also be done with the help of a multimeter.

Pinched wires are a common problem with DeWalt push mowers and can prevent the mower from starting. When the handle is folded into the machine, it creates a tight space that can easily pinch a wire.

Using a wire nut, you can fix any connections that have become loose or pinched. Take out the battery before you start fixing it.

You should also contact DeWalt to see if the warranty you purchased is still valid. If you attempt to fix a frayed wire on your own, you may void the warranty.

The Rotation of the Blade is Being Restricted by Debris

Excess grass and other debris can easily become stuck under the deck of a lawn mower.

Check the area under the deck of your zero-turn or push electric lawn mower, close to the blades, to see if any debris has accumulated and needs to be removed.

Always remember to take out the batteries before you start working on the deck.

If your electric lawn mower is reluctant to start, a buildup of grass in the deck may be preventing the blade from turning.

Your lawnmower’s safety measures will prohibit it from starting if the blades can’t spin freely.

Overloading your DeWalt mower might cause it to stall mid-mowing or even prevent it from starting. This occurs when too much grass is being chopped at once, especially if the grass is particularly thick, tall, or damp.

If you’re encountering this issue, try increasing the cutting height of your mower and going at a slower speed.

Broken Parts

If you’re having problems getting your mower to start, you might be looking at an expensive repair.

Components on your lawnmower will eventually wear out and need to be changed; this is an unavoidable fact of life.

Some parts wear out quickly and can be changed at little cost, but the expense of replacing the most problematic part and paying for any necessary repairs could exceed the value of the lawn mower itself.

Therefore, you should inspect your lawnmower’s parts and decide if it’s worthwhile to repair it based on the extent of the damage.

Here are some of the more frequent electric lawn mower replacement parts:

Batteries, plugs, switches, and blades

Most of these parts have already been covered, along with an explanation of why a broken or misaligned one can prevent your lawn mower from starting.

The start switch and the motor are two important parts that we haven’t discussed in depth yet.

If you find that either of these components is broken and is most likely the reason why your electric lawn mower won’t start, you should definitely take it to a professional repair shop rather than trying to fix it yourself.

These parts are not only dangerous to work with unless handled by people with substantial mechanical and electrical understanding, but they can also be rather costly.

For Warranty Service, Please Contact DeWalt.

Contact DeWalt customer service for warranty repairs if your mower is malfunctioning while still covered by the manufacturer’s warranty.

If you have any questions or comments, please contact them at 1-800-4-DEWALT (1-800-433-9258) or through their website.