The John Deere mower won’t start (Find Out Why)

Now that spring has arrived, it’s time to get the lawnmower out again and cut that crazy tall grass. You go to start the mower, but nothing happens this time. You can’t even get your mower to start.

If your John Deere lawnmower won’t start, check the battery, cables, connections, fuse, ignition switch, safety switch, starter solenoid, and starter itself.

Avoid getting electrocuted by taking precautions when working on your lawn mower’s electrical system. Always refer to the operator’s manual for guidance on how to use the device safely. If you are unsure of how to perform troubleshooting and repairs, it is recommended that you contact a professional mechanic.

The John Deere mower
The John Deere mower

Before diagnosing, repairing, or operating, make sure you’ve read and understood all of the safety instructions in the equipment’s operator’s manual. If you don’t feel confident in your ability to make the necessary repairs, whether due to a lack of experience or health, you should get in touch with a professional.

Troubleshoot: John Deere Mower Won’t Turn Over

  • Check for a dead battery
  • Check for a bad ground, corrosion on the terminals, and dangling wires.
  • Look for a blown fuse
  • Check for a bad safety switch
  • Check for an ignition switch failure
  • Check the starter solenoid
  • Have your starter motor tested and replaced if needed

Why Is Your John Deere Mower Not Turning Over?

Your John Deere lawnmower’s battery may be dead or defective.

In the absence of a charged battery, a John Deere lawn mower will not start. Initial steps consist of using a multimeter to determine the battery’s state of charge.

You should see around 12.7 volts from a fully charged 12-volt battery. If the reading is low, try giving the battery a charge. The article “5 Things That Are Draining the Life of Your Lawn Mower Battery” includes instructions on how to conduct a battery test. The factors that can result in your battery draining are also discussed here.

Charging a Battery: If you need to charge your battery, use a battery charger. Before you go any further, make sure your eyes and skin are protected with safety goggles and gloves. To use a charger on your John Deere battery, do as follows:

  • Get at the terminals and battery. To access the battery, you may need a screwdriver. Avoid taking the battery out of its case.
  • If you’re using a charger, the positive cable should go in first. In other words, this is the red cable or the “plus” cable. Connect the cable to the battery’s positive terminal.
  • Join the negative end of the cable to the battery’s negative post. In other words, this is the negative-sign cable (also known as the black cable).
  • To avoid electrocution, avoid touching anything that isn’t covered in rubber.
  • Make the appropriate adjustments to the charger’s output voltage and current. Standard lawn mower batteries typically have a voltage of 12 volts. Higher current speeds up the battery’s charging process. The recommended starting point is 2 amps, with a maximum of 10 amps. What’s ideal is a gradual charging process.

A new battery should be installed if the old one is unable to maintain a charge. A replacement battery can be purchased from any local automotive shop, hardware store, or lawn mower dealership.

If you have an old battery, please bring it with you. If you don’t bring in your old battery, most stores will charge you a core fee.

Loose Wires and Connections on Your John Deere Lawn Mower

Wires and connections on lawnmowers are notorious for becoming dislodged and unplugged. This is because wires can become disconnected when they become dislodged from the John Deere’s vibrations and no longer provide a solid ground.

It’s not enough to simply check for and secure any dangling wires; you also need to look for corrosion in any connections or wiring. Corrosion brought on by humidity threatens to disrupt the smooth functioning of the system.

Use a baking soda solution to eliminate the rust (2 cups water to 3 heaping tablespoons of baking soda). Tighten up all of the wires and plugs.

Wires, connections, and terminals should be replaced if you find any signs of damage or severe corrosion.

Bad Fuse on Your John Deere Lawn Mower

An electrical safety device known as a fuse can be found on your John Deere lawn mower. Verify that the fuse hasn’t blown.

The resistance between the probes of a multimeter and the fuse’s prongs can reveal whether or not the fuse has blown. If the resistance reading is close to zero, your fuse is fine. A blown fuse will show up as infinite resistance.

If a fuse blows, you must replace it with another fuse that has the same amperage. Never switch to a lower amperage.

If you have a John Deere mower and keep having fuses blow, you should take it to a repair shop or a John Deere dealership.

Bad Ignition Switch on Your John Deere Lawn Mower

When turning the key in the ignition of a John Deere and getting no response, the problem may lie with the ignition key switch. The mower will not spin over or start.

If you suspect the ignition switch is broken, you can test it with a multimeter to see if there is any continuity. To do this, locate the “B” and “S” prongs on the battery and the starter solenoid, respectively.

Place the key in the lock and turn it until you reach the “start” position. Set the multimeter’s resistance measurement mode and touch the B prong with one probe and the S prong with the other.

The resistance of a high-quality key switch for the ignition should be close to zero. If the resistance reading from the ignition key switch is infinite, it’s time to get a new one.

Bad Safety Switch on Your John Deere Lawn Mower

The operator of a John Deere mower is protected by multiple switches. If certain conditions are not met, such as when the brake is engaged, the mower will not start because of these switches.

A faulty safety switch can prevent a John Deere from starting. Apply the multimeter test to your switch. The safety switch can be temporarily disabled during troubleshooting to help pinpoint a faulty unit.

Put the safety switch on before you start mowing.Never use a lawnmower with the safety switch disabled. You never know when you might need a safety switch, but having one is always a good idea.

Bad Starter Solenoid in Your John Deere Lawn Mower

When the ignition key is turned, an electromagnetic switch called a starter solenoid activates the starter motor, which in turn starts the John Deere’s engine.

When the starter solenoid’s internal spring weakens or the copper plate corrodes, the device can malfunction. If the starter is weak, the battery is dead, or the ground is corroded, the solenoid won’t work.

You need to make sure the battery is fully charged before trying to test the starter solenoid. Continue testing the solenoid with the methods detailed in “How to Tell Your Lawn Mower Solenoid is Bad” for identifying a faulty starter solenoid.

Bad Starter Motor on Your John Deere Lawn Mower

After checking the battery, cables, wiring, ground, and starter solenoid with no success, you should check the starter on your John Deere. It’s possible to take out the starter and put it through its paces.

Before you go out and buy an expensive new starter for your John Deere mower, I suggesthaving your starter checked out and possibly rebuilt by a local repair shop that specializes in starter and alternator repairs.

Your John Deere lawnmower is still giving you problems, right?

You, the owner of a John Deere mower, will run into a wide range of issues throughout the course of its service life. Problems with starting, shutting off mid-mowing, vibrating excessively, cutting unevenly, or simply not moving are all possibilities.

I made this handy John Deere mower troubleshooting guide to assist you in determining the source of your lawnmower’s issues. For help with your John Deere lawnmower, read “Common Issues and Fixes.”