The only lawnmower troubleshooting guide you’ll ever need.

Dad's guide for when your electric lawn mower is not starting

A look out into the countryside reveals that it’s time to mow the lawn again. Your neighbors have always envied you when working with your electric lawnmower. You like how fresh your garden smells and how seamless grass mowing has always been for you. No gas smell. No oil stains or pollution while mowing your garden. And of course, no spark plug problems or clogged air filters. Except the lawn mower is not starting now!

Like any mower, your electric mower is not immune to breakdowns. But nothing is more frustrating than being stuck on the patch of grass with a mower that refuses to start. Stop cussing at the poor thing. Instead, I’ll give you some electric lawn mower troubleshooting tips so you can have the machine revving back to life.

Common causes when your electric lawn mower won't start up

Before suggesting the electric lawn mower troubleshooting tips, I’ll start by helping you make a diagnosis of the problem.

By knowing the main reasons the electric lawn mower is not starting, you will be able to identify the problem and repair your machine.

1. The capacitor is faulty

If the electric lawn mower’s motor is not starting, this may be due to a defective capacitor.

This component is responsible for driving the engine by storing energy and delivering it to the engine.

Typically, the capacitor is located outside the motor, often in a metal-covered box. As this is a wearing part, this can be the very reason why your lawn mower will not start.

2. Check for a Defective electrical cord

If you use an electric lawn mower, in most cases, you need a cable to supply your device with power.

The disadvantage, unlike cordless mowers, however, is the lawn mower will not start when the cord wires are broken.

While not being very careful, you may have run over it with the lawnmower. Then the blades damaged the cable.

The cable could have also broken from the inside if you wound it up incorrectly. It is also possible that some rats in the garden or garage have nibbled on it and, therefore, no current is flowing through.     

3. The circuit breaker may be activated

Some models of electric mowers have an electrical safety system called the circuit breaker or thermal protector. This protects the motor and the user. 

It automatically cuts the circuit in the event of overheating or electrocution which can sometimes activate without you realizing it.

This could be because:

  • The blade is blocked by something
  • There’s too much grass or debris accumulating under
  • The motor has overheated, for example, due to an overload of motor power
  • The mower has been tilted too much.

This protection can sometimes cause your mower to not start again. If it does not reset, the circuit breaker must be manually reset.

Try restarting the machine after a few minutes. If the protection has not been removed automatically, then you need to make a manual reset. This troubleshooting will be indicated in the instructions for using the mower.

4. Check the Battery

If you have a cordless electric mower, the most common failure is from the battery, which can have a longer or shorter life depending on use.

Okay, wait! I’m not saying the battery could be bad, and neither am I saying it couldn’t be. However, the metal contacts on the battery may be covered by sulphur buildup or rust.

On the other hand, you could have a drained battery. When the temperature goes below 40 degrees Fahrenheit, the grass becomes dormant and barely grows.

Then you end up packing up the mower until spring. Even when you don’t need to mow, make it a habit to warm your mower a few times during winter.

Also, note that the battery can wear out with age or humidity, for example, after long storage in a damp place. It will then simply be necessary to replace the battery.

5. The blades are blocked

A common reason lawn mowers don’t start is when the blades are blocked or bent by debris buildup. When too much stuff builds up under the blades, or sometimes in the collector, the mower can jam, and the engine can hardly or not start at all.

Depending on the mower model and the type of power, some electric mowers can no longer start because the motor is overloaded by too much mass: grass debris, wood, branches, rocks, wet grass, large leaves, or rods.

Depending on the type of terrain and how the housing and the blade of the mower are constructed, debris can quickly accumulate around the blades and thus cause starting failure.

This problem can sometimes be spotted before the breakdown when the engine makes an unusual noise: it hums, purrs, or idles.

This problem can sometimes be spotted before the breakdown when the engine makes an unusual noise: it hums, purrs, or idles.

6. Water entered the engine and caused a short circuit

When water gets into the engine, the lawnmower may not start. Water may enter the motor through openings in the lawn mower and cause a short circuit.

This is so problematic because in such a case, the lawnmower has to be repaired by a professional. There is also a risk of getting an electric shock.

You can try your luck and let the lawn mower dry in the sun (with the engine flap open). If that doesn’t work, a professional must check the device.  

Dads guide to lawnmower troubleshooting.

While trying to fix your electric lawnmower that won’t start, here are a couple of things you should check:

1. Change the capacitor

You must first ensure that the battery is properly connected and charged for the mower to work. If it does and the mower still won’t start, the problem may be with the switch.

Check that the wires are in place on the battery system. If not, put them back in place and tighten them.

If the switch and the battery are in bad condition, change them.

2. Test the charger

The charger may be the cause of the start failure. First, plug it into another socket. Check to see that one of the LED lights is on. This will help you whether the charger is supplying power. If not, the charger should be tested.

Plug it in and get your multimeter. Put it in the voltmeter position on 20 V.

With the pin of the multimeter plugged into “COM,” press down on the metal slide on your charger marked with the “minus” symbol and the other with the “plus” sign.

If you don’t have a value, your charger is faulty and needs to be changed.

3. Test the power cord

You may open up your power cable and test the continuity of the two main wires separately. To do this, set your multimeter in ohmmeter mode to 200 Ω (Ohms)

Position one tip of your multimeter at the end of the power cable and the other at the other end.

Make sure the pins of the multimeter are in contact with a metal part.

If no value is displayed, then the faulty cable must be changed.

Electric lawn mower is not starting

4. Test the power outlet

The failure may come from the mains connection used for the device.

Check that the socket is in good condition. You can plug another functional device into it, like a lamp or a phone charger. If the device works, the socket is in good condition.

Check that the socket is not wet or burnt. Examine the end of the cable that you plug into the socket. Make sure there are no burn marks or black spots.

You can also electrically test the socket with a multimeter:

  • Set your multimeter to the highest range in AC mode.
  • Then place the test probes in the socket. If you find a value close to 230 volts, the outlet is not the cause of the fault.           

Possible Solutions when an electric lawn mower is not starting

In some cases, a lawnmower is really not complicated to fix! 

Let’s try here to see a non-exhaustive list of the possible solutions for an electric mower that does not start.

1. Change the capacitor

The replacement capacitor can be obtained for a relatively low price. But you still need a specialist to carry out the replacement.

The capacitor is an energy store that can still hold power when the lawnmower is disconnected from the mains.

You might be seriously electrocuted if not careful, especially if you’re the type who tests batteries and capacitors with the tongue for leftover voltage. Taking the machine to the workshop is therefore advisable.

2. Remove blockade or change the blade

As I mentioned, a blocked blade means the mower won’t run. You only need to unblock the blades by cleaning and dislodging the grass or the debris, residues, and other objects stuck in.

Meanwhile, before you start, ensure you’ve switched off the mower and triggered the safety switch to avoid accidents. 

In the worst-case scenario, all you have to do is change the blades. First, however, the device must go to the workshop if the crankshaft is bent.

You can also change a lawn mower blade, as the replacement is not very complicated. However, you need to be careful. A blade that does not fit the device can cause major damage.

In addition, you must disconnect or turn the unit off so that the engine does not start while working on the blade with your hands.

Using work gloves are also important, so you don’t accidentally cut yourself but gloves won’t prevent crushing of fingers should the blades start turning without warning. Serious injuries are imminent here, which is why professional help is recommended.

3. Fix the defective switch

The element that generally causes the failure is the switch, the part located in the box with the ignition button.

Sometimes, with wear, vibrations, humidity, oxidation, or even a badly placed blow, a bad contact can cause the malfunction of the switch. In some cases, this element itself will have to be replaced.

If you suspect that the switch may be the problem, open the switch box to check the condition of the electrical components and wires.

You may remove the switch to connect a new one. Ensure you reconnect everything as they were. But this is a job that can sometimes be entrusted to a repairman.

Electric lawn mower is not starting

4. Fix all possible power problems

If electricity no longer goes to the machine, it will not start. You should check the extension socket, where the extension cord is connected to the mower

This socket usually has its fuse, and if it is blown, it can cause the starter failure. Plug the mower in another socket to see if it starts.

If it is neither the blocked blades, nor the circuit breaker which has activated the switch, nor a problem with the power supply, then the motor may have a problem.

It’s kind of the least desirable scenario, as it may take more trouble to fix. But if you’re a bit of a handyman, you can always open it up.

Check if the fuses are ok or if the belt isn’t broken. You may also use an electrical tester to check that the connections between wires and elements are good. See if the components are not oxidized.

However, recent models with more elaborate circuits and electrical components can be difficult to troubleshoot. If you suspect the problem may be with the motor, then you should take the mower to your nearest dealer or DIY store.

A repair on the cable should preferably be done by a professional, as the risk of injury from an electric shock is great

Conclusion

That’s it. When your electric mower is not starting, there are some common causes.

The blades may be blocked, and the motor does not start anymore. The thermal protection may have activated, and the circuit breaker prevents the unit from starting. The switch may be defective. Finally, there may be a problem with the power supply: the extension cord, mower plug, mains plug, or battery.

Depending on the problem, you may be able to restart your electric mower after some time or by changing a part.

In all cases, it’s useful to have a voltmeter or multimeter when you have an electric lawn mower. It allows you to see where there is a lack of electricity, check why the engine does not start, and also be used in the maintenance of any electrical device.

If, in the end, you’ve tried everything, your mower won’t start, and you’re looking to shop for a new electric one, check out our Dad’s guide to top things to consider before buying a new electric lawnmower here.