Why Lawn Mower Has no Electrical Power? Causes and Fixes Explained

Nothing is more frustrating if your lawnmower does not start due to a lack of electrical power. 

There are several common reasons why your lawn mower has no electrical power. Most of these problems are battery-related and simply changing the battery can resolve the problem.

If you have a functioning battery and still facing power loss, read this article to know more about what else can cause you this problem. And here you will find the corresponding solutions to power your lawn mower up.

6 Reasons for Lawn Mower has No electrical Power and Their Fixes

There can be several reasons why your lawn mower may not have electrical power. Here are the reasons and the fixes that you can do all by yourself:

1. Battery Issues:  

One of the most common culprits behind a lawn mower’s lack of electrical power is a battery-related issue. Let’s explore some potential battery problems and their corresponding solutions.

If your lawn mower’s battery is completely dead, it won’t be able to provide the power to start the engine. This can occur if the battery is old, has been drained due to long times of inactivity, or if there is a problem with the charging system.

• To fix the battery issue, check the battery voltage using a multimeter. A fully charged battery should read around 12.6 volts. If the voltage is significantly lower, it may indicate a dead battery. 
• Charge the battery using an appropriate charger.
• If the battery voltage is low, try jump-starting the mower using jumper cables and a functioning battery from another vehicle. Once the mower starts, allow it to run for a while to recharge the battery.
• If jump-starting doesn’t work, you may need to replace the battery. 

Another battery issue can be loose or bad battery connections. Bad connections can hamper the mower’s ignition system, resulting in a lack of power.

To fix the connections:

• Disconnect the battery cables and clean the battery terminals using a wire brush to remove any corrosion or debris. Over time the terminals get rusted and can hamper the current flow. So make sure you have clean battery terminals.
• Reconnect the battery cables securely and ensure they are tightly fastened to the battery terminals.

2. Faulty Ignition Switch: 

A faulty ignition switch is another reason why your lawn mower has no electrical power and fails to start the engine. There can be many reasons why your ignition switch gets bad. 

To troubleshoot a faulty ignition switch, follow these steps:

• Check if the ignition switch is loose or if there is any visible damage. If so, replace the switch.
• Test the ignition switch using a multimeter. Consult your mower’s manual or an electrical wiring diagram for the correct pin connections and expected readings. You can diagnose this from a professional. 
• Open the fuse box and check the fuses visually. Look for any signs of a blown fuse. A blown fuse can also prevent power from reaching the ignition system of the lawn mower.

3. Faulty Control Module: 

Nowadays most mowers have a control module that has a circuit with relays and resistors. The control module’s job is to receive a start/stop instruction from the ignition switch and to send a start command to the starter. 

So, if anything on the circuit has a fault that can lead the mower to lose power.

If you discover any kind of problem on the circuit, you have to change the whole thing. Sometimes changing the faulty part can fix the problem but, in most cases, you need to change the whole circuit. 

It is a bit expensive to change the circuit and you will need a professional to do that. 

4. Loose Wiring:  

Loose wiring connections can disrupt the electricity through the circuit and that leads to your lawn mower has no electrical power.

It happens when you mow uneven surfaces a lot. Over time the wires get loosened up and cut the connection.

Fix

It is very simple to fix but you have to find where the wiring connected got loose.  After finding it change the wires, clean the corroded terminals, and ensure all connections are tight and secured.

5. Faulty Safety Switches: 

Lawnmowers are equipped with various safety switches that prevent the engine from starting if it detects any problem. If any of these safety switches are faulty or not engaged properly, they can cause a loss of electrical power.

To fix this you have to know how many safety switches are there in your mower and where you can access them. Usually, in a mower, there are 3 types of switches. Seat switch, blade engagement switch, and brake switch.

Change the switches if you find any visible damage and make sure to connect the wires tightly.

6. Bad Solenoid: 

The solenoid is responsible for engaging the starter motor when the ignition switch is turned ON. A defective solenoid can prevent power from reaching the starter motor, resulting in a lack of electrical power.

To fix a defective solenoid, follow these steps:

• Locate the solenoid on your mower. It is usually mounted near the battery or starter motor.
• Check the solenoid for any visible damage or loose connections. Replace the solenoid if necessary.
• Test the functionality of the solenoid using a multimeter. Follow the manufacturer’s instructions or consult an electrical wiring diagram for the correct pin connections and expected readings

Lawn Mower Has No Electrical Power: General Troubleshooting

In addition to the specific issues mentioned above, here are a few general troubleshooting tips that can help to fix when your lawn mower has no electrical power:

• Check the key switch: Ensure that the mower’s key switch is turned to the “On” position and that the key is inserted properly.
  
• Inspect the wiring harness: Look for any visible damage or loose connections in the wiring harness, especially in areas exposed to vibrations or excessive heat.
  
• Test the voltage regulator: If your mower is equipped with a voltage regulator, test its voltage using a multimeter. Replace the voltage regulator if you see any damage.
  
• Consult the manual: Always refer to your mower’s manual for specific troubleshooting instructions and safety precautions. 

Frequently Asked Questions (FAQs):

Why is there no power in my lawn mower?

There are many reasons why your mower has no power. The most common reason is s dirty air filter on your lawn mower. Over time the air filter gets dirt and debris that make your mower lose power.

Why does my lawn mower do nothing when I turn the key?

If nothing happens when you turn the key, that means the mower has an electrical problem. Check all the connections on the battery. Make sure the battery has a full charge and the ignition system is working properly.

Are lawn mowers 12V or 6V?

Some lawn mowers use 6-volt batteries but you might see the charger you are using to charge the mower is 12-volt. It is normal as the charger needs to be more volt than the battery to have better efficiency.

How many volts does a lawn mower produce?

12.6 volts. Riding mowers use a 12.6-volt electrical system.