When your Cub Cadet riding mower or zero-turn won’t even click when you go to start it, it’s time to look at the electrical components.
The most common causes are a dead battery, loose wiring, or a bad ignition switch. However, there are many other items that can prevent your mower from starting including the safety devices used in the operator presence system.
I’ll go through the rest of the items you should check when you find yourself in a situation where nothing happens when you turn the key.
Follow all safety instructions provided in your equipment operator’s manual before diagnosing, repairing, or operating. Consult a professional if you don’t have the skills, or knowledge or are not in the condition to perform the repair safely.
Other articles that may help with your Cub Cadet Starting Problem:
- You hear a clicking or humming sound, but the mower won’t start
- Why your battery keeps going dead
- Symptoms of a starter solenoid and how to troubleshoot
1. Dead or Faulty Battery
First things first. Check the battery. The ignition system uses power from the battery to power the solenoid to turn over the battery. So, it’s best to start by checking the battery using a multimeter.
A fully charged 12-volt battery should provide you with a reading of 12.7 volts.
There are a couple of ways to charge a dead battery. The best way is to slowly charge it using a battery charger.
However, you can also attempt to jumpstart it using a car battery using jumper cables. With this method, once the mower starts, you’ll need to continue to operate the mower to let the mower continue to charge the battery.
Charging a Battery: Use a battery charger to charge your battery. Before you continue, wear protective gear to protect your skin from electrical shock and protect your eyes. Follow these steps to charge your riding mower battery with a charger:
- Access the battery and terminals. You may need to use a screwdriver to uncover the battery. You will find the battery under the hood or under the seat. Do not remove the battery from the casing.
- Connect the battery charger cables beginning with the positive cable first. This is the red cable or the one with the plus sign. Place the cable on the positive battery terminal.
- Attach the negative cable to the negative battery terminal. This is the black cable or the one with the negative sign.
- Do not touch anything that doesn’t have a rubber coating to prevent electrocution.
- Set the charger’s voltage and amperage level to the desired level. The average volt level for lawn mower batteries is usually 12 volts. More amperage charges the battery faster.
- Start with two amps and work up to no more than 7-10 amps. A slow charge at 2 amps is best, but it will also take longer to achieve a fully charged battery. You’ll have to put off mowing for a day while it charges.
If you find your battery won’t hold a charge, it’s time to replace it with a new battery. You can purchase lawn mower batteries at your local hardware or automotive store.
Remember to bring your old battery with you or you’ll be charged a battery core fee at most places.
2. Loose Cables, Wiring, and Connections
A loose cable, wiring, or connections can cause your Cub Cadet to not start. Check these items and the terminals for corrosion. Remove corrosion using a baking soda and water mixture.
Follow the cables from the battery and check the wiring leading to your electrical components including the ignition switch, safety switches, and control module.
Make sure the wiring and cables are not damaged or corroded. They must make a good connection with the components.
3. Wrong Starting Procedure
Cub Cadet requires certain procedures to be met before the engine will start. This is put in place for your safety so the mower doesn’t accidentally start.
I have listed the most common safety features you will find on your mower. All of these items must be in the correct position for the engine to start. If not, most likely nothing will happen when you turn the key.
Brake is Not Engaged
The brake must be engaged before turning the ignition switch to start the engine.
- Cub Cadet riding mower and lawn tractor: depress the foot pedal brake. If you don’t have a foot pedal brake, the brake may be a lever located just below the steering wheel.
- Cub Cadet zero turn mower: depress the foot pedal brake. If you don’t have a foot pedal brake, the brake may be engaged when the driving arms are in the outward position.
Not Sitting in the Seat
You must be sitting in the seat for the mower to start. Make sure you have your weight centered on the seat and that you’re not sitting too close to the front of the seat so you engage the seat switch.
PTO is Engaged
The PTO (power take-off) must be off. This is the knob or lever that is used to turn on the mower blades. You’ll have one of two types of PTOs:
- Electric PTO: A knob is depressed to turn the mower deck off. It must be in off to start the mower. Pull up on the knob once the mower has started and you’re ready to engage the cutting deck to mow the lawn.
- Manual PTO: The PTO lever must be pushed forward to engage the cutting deck. You want the PTO pulled backward to the off position to start the mower.
4. Bad Safety Switch
Each of these safety items has an on/off type of switch. These are the switches that indicate whether the safety measure has been satisfied for the mower to start.
A safety switch can be defective and cause a mower to fail to start. Test the switch using a multimeter. You can also temporarily bypass the safety switch to identify a bad switch but only do this for troubleshooting purposes.
If the switch tests well, make sure the plate is making a good connection to engage the switch.
Never operate a mower without the safety switch. Never run a mower when a safety switch is bypassed. A safety switch can save you from serious injury and you never know when you’re going to need it.
5. Bad Ignition Switch
The ignition key switch can be the culprit when your Cub Cadet mower doesn’t do anything after you insert the key and turn it.
While key switches do vary by model, here are instructions for a common key switch.
- Check the switch using a multimeter to check continuity to determine if the ignition switch is the problem. To do this, look for the prongs marked “B” for Battery and “S” for Starter Solenoid.
- Insert the key and turn it to the start position. With the multimeter set to measure resistance, touch one probe to the B prong and the other probe to the S prong.
- A good ignition key switch will measure resistance near 0 ohms. A bad ignition key switch will measure infinite resistance and will need to be replaced.
6. Fuse is Blown
A fuse is installed on your riding mower to protect the electrical system. You’ll want to check to make sure you don’t have a blown fuse.
If you’re unsure if the fuse is blown, you can check it by placing a multimeter probe on each prong of the fuse to measure resistance. A resistance reading near 0 means your fuse is good. An infinity resistance reading indicates a bad fuse.
When you find a blown fuse, you must replace it with a new fuse. Replace the fuse with the same amperage as the one you are replacing. Do not use a different amperage.
Take your mower to your local Cub Cadet dealer or mower repair shop if you continue to blow the fuse to find and repair the root cause of the problem.