I’ve had the issue that my electric lawn mower won’t shut off a couple of times. With a little investigation, the problem turned out to be the power switch. Power switch, what power switch? Well, the one that should start and stop your lawn mower when you pull the lever on the handlebar. Sound familiar? No? Well, let’s take a closer look at power switches and figure out if it’s the reason your lawn mower won’t shut off.
Electric Lawn Mower Won’t Stop (Overview)
Part of your electric lawn mower’s electrical circuit is the power switch. The power switch is located on the handlebar and is designed to start and stop your lawn mower when pressed or released. If your electric lawn mower won’t shut off, it means the power switch is not released when the power lever is released.
What is a Lawn Mower Power Switch?
The power switch on your lawn mower closes the circuit when pressed and opens the circuit when released. These types of switches are also known as push-button switches and tactile switches.
Your lawn mower uses this type of switch primarily as a safety feature. For example, the motor stops if you let go of your lawn mower. So, if your lawn mower is left unattended, the electrical circuit breaks, and the cutting blade stops spinning.
In addition to this feature, the momentary switch makes operating an electric lawn mower much simpler and more efficient than a typical on/off switch that needs to be physically turned ON/OFF.
How a Lawn Mower Power Switch Works
A lawn mower power switch is switched ON by the power lever on the handlebars. In other words, when you pull the power lever on the handlebar, the lever presses the switch into the ON position. When you release the lever, the switch’s internal spring returns the switch to the OFF position and breaks the electrical circuit. Well, at least that’s what should happen when it’s working correctly.
What Causes Problems With Electric Lawn Mower Power Switches?
Probably the most common reasons a lawnmower’s power switch fails is corrosion or debris obstructing the movement of the switch mechanism. Things like incorrectly washing or storing your electric lawn mower can allow water into the switch mechanism and cause corrosion. As for the switch jamming with dirt and debris, this can happen with just general wear and tear.
Therefore, even with the best efforts to avoid these issues, your lawn mower power switch can fail, resulting in the spring not returning the switch to the OFF position, and your mower won’t turn off.
Other Power Switch Problems (Electric Mower Won’t Start)
Along with a switch that won’t turn off, the opposite can also happen. Your lawn mower power switch won’t turn on. Again, this usually happens when corrosion and debris get into the switch. The only difference is that instead of the switch not turning OFF, it won’t turn ON.
Additionally, a switch won’t turn ON for other reasons, such as corroded power switch connections, a shorted switch, or a defective power switch lever. So, it is worth taking care of the power switch mechanism to avoid these problems.
Are Corded & Battery Powered Lawn Mowers The Same?
Corded electric lawnmowers and battery-powered lawnmowers both have power switches. This is because both types of lawnmowers rely on electricity to power the motor and need the same safety features and convenience. So, an electric lawn that won’t turn OFF can happen to either battery or corded mowers.
Why You Should Always Repair an Electric Lawn Mower Power Switch
Now, there are ways around a power switch that won’t turn off, such as pulling the power cord out or removing the battery. But this is a bad idea because having your mower’s safety feature is important. For example, if you trip and your lawn mower doesn’t stop, you run the risk of a potentially fatal accident. Now, without going into too much detail, spinning mower blades and body parts don’t go well together. So, my advice is to repair your lawn mower immediately.
How to Test a Lawn Mower Power Switch
To determine if your power switch is at fault, you’ll need to remove it from your lawn mower and test its operation.
Here are the steps to test your electric lawn mower power switch:
- Disconnect your lawn mower power source.
- Remove the power switch & power lever housing cover.
- Remove the power switch from its mounting position.
- Manually press and release the switch button a few times.
If the switch stays in the ON/IN position, then the switch is faulty and should be replaced.
If your switch works, the button should press in and spring out without a problem. Therefore, you’ll need to inspect the switch/lever housing and the lever mechanism, as the problem isn’t with the power switch.
Tools & Parts To Replace A Lawn Mower Power Switch
You’ll only need a few tools and parts to replace your power switch. Tools include a screwdriver to remove the power switch housing cover and a pair of pliers to remove the connections from the power switch. Following this, you’ll need a replacement power switch. Now, power switches are specific to specific lawnmowers. So, you’ll need to purchase a replacement specific to your lawn mower’s make, model, and year. Once you have everything, you can tackle installing the replacement lawnmower power switch.
Steps to Replace A Lawn Mower Power Switch
Half of the work for replacing the power switch in your lawnmower is the removal and installation of the power switch housing cover. In addition to this is the removal of the switch from its housing. So, all that is left is replacing the power switch.
You’ll need to remove all the connected wires to replace the switch. I try to do one at a time so that I don’t get the wires mixed. Or I take a picture before I start. This gives me a reference just in case one of the wires falls off unexpectedly.
Depending on your specific replacement switch, you may have push-on spade-type connectors or push-in connections that need the wires pushed into the switch. These push connectors can be fiddly, so a pair of pliers will probably come in handy.
Once you have swapped the wires into your replacement switch, position the switch into the housing and replace the cover. That’s all there is to it. Hopefully, your electric lawn mower will turn ON/OFF as designed.
Other Lawn Mower Electrical Issues
Electrical issues are not just limited to the power switch. Many other problems can stop your electric lawnmower from functioning correctly. Here are some examples, including links to some of my other blogs:
- Incoming Power – problems with the incoming power ranging from outlets to breakers.
- Cables & Extensions – Power issues lost through damaged cables.
- Power Source Connection – Corrosion & defective power connection to your mower.
- Electrical Connections – Loose and corroded electrical connections inside your mower.
- Thermal Cut-Off Switch – Defective thermal switches stopping your electric motor
- Power Rectifier – AC power not being converted to DC power
- Motor Brushes – Worndown carbon brush stopping power from getting to the motor.
