You save time and effort when you clean with a functional power washer. Karcher is a well-known brand of reliable power washers. It's a hassle if you need the washer, and it doesn't turn on. In this post, we will help you understand why a Karcher pressure washer won't turn on.
A Karcher pressure washer may not turn on due to the following:
- Broken power button or front cover
- Defective electrical cord and power outlet
- Tripped circuit breaker or GFCI
- Blown fuse
- Excess air pressure in the hose
- Defective parts
These issues will vary depending on the type of washer you have. Some solutions will not require you to fix critical components. If the issue is technical, let a professional inspect the electrical parts. Continue reading to learn about these problems and how you can solve them.

Why Won't My Karcher Pressure Washer Start?
Karcher is one of the leading makers of cleaning devices. But if you don't use your Karcher washer properly and follow the instructions, it might not work as expected. Internal and external parts can get damaged due to improper use.

Broken Power Button And Front Cover
Regardless of the power source, the problem with the washer might be due to a broken power button and front cover. These parts are vital in operating the washer.
To solve the issue, you should disassemble the machine and replace the defective button and damaged front cover..
Electric-Powered
Karcher pressure washers run by electricity or gas, so the causes of the power not turning on will vary. If the washer runs on electricity, you need to check the following:
- Check if you plugged the electrical cord into the outlet.
- Make sure the outlet isn't defective.
- When you have properly plugged in the washer and determined that the parts are working well, check for a tripped circuit breaker. This can cut off the power to the washer. Likewise, the GFCI of the washer might have tripped.
- Check for a blown fuse.
- If the pressure washer detects air in the hoses, it will not function well.
- If the machine makes a humming noise but the motor has quit, the reason is a defective capacitor.
While solving any of these issues, be careful when you work on the electrical components.
Gas-Powered

For gas-powered models, listed below are the components that affect their function:
- Defective spark plug due to cracks, heavy carbon build-up, and damaged or burned electrode
- Clogged carburetor
- Ignition coil fails to send voltage to spark plug
- Halved flywheel key caused by high pressure hitting a hard object
If there are critical electrical components to replace, you should take the unit to the manufacturer's service center for inspection. Karcher wants users to be safe, so they do not recommend DIY repair of electrical components.
Solutions To Start The Pressure Washer
Now that we've covered the various problems encountered by a power washer, you have an idea of which parts to work on. Try the solutions listed below to get your power washer started.
- Plug the cord of the washer into a working outlet. Make sure that the outlet is functioning.
- If the problem is with the extension cord, you can plug it into other machine and see if it works. The cord might be incompatible with the power washer if it does not. Purchase the recommended cord for your Karcher washer model.
- Use a multimeter to check if the unit's electrical capacity is within range.
- Also, test the GFCI once a month, and reset it before using the device.
- Press the RESET button on the power outlet if the washer model has one.
- Replace the defective components if these are beyond repair.
- Take the unit to a service center. After the assessment of a technician, the unit might need a complete overhaul.
For hoses filled with air, below is the process:
- Turn off the water supply and the washer.
- Attach a garden hose to the water input port.
- Then attach the high-pressure hose to the water outlet. Remove the spray wand on its end.
- While the washer is off, let unpressurized water flow through the hose for five minutes.
- Afterward, return the spray wand. Repeat the previous step while pulling the trigger of the wand tip to release the excess pressure.
- Switch on the pressure washer and use it.
Do not use the power washer if these solutions fail. You should contact Karcher customer service to help you with the problem. You can also reach them through their website and submit a ticket for your concern.
How To Turn On A Karcher Pressure Washer
If you have tried the solutions mentioned above, try turning on the device. The steps for starting it will differ if the machine is electric or gas-powered.

Electric-powered
The process is easy for this type of washer. Here are the steps:
- Attach the garden hose connecting the water supply and the washer.
- Insert the high-pressure hose between the spray wand and washer.
- Turn on the water supply.
- Hold down the spray wand and expel water and air from the washer.
- Continue holding the trigger to remove the pressure build-up while you switch to the ON position.
Gas-powered
With this type of machine, the process is more complex because you need to fill the engine with oil and gas. Before you proceed, you should buy the proper grade of oil and gas for the machine. Check the manual for the filing instructions.
After buying the oil and gas, follow the process below:
- Allow air to vent out from the pump by cutting the tip off the yellow plug located at the top of the pump.
- Follow steps 1-3 above when turning on an electric-powered washer.
- For some models, you need to regulate the gas line to fill the engine with fuel. Also, regulate the choke to allow air into the engine.
- Hold down the trigger of the spray wand to remove the pressure. While doing so, also pull the engine start cord.
- Once the engine starts, regulate the choke to the closed position to cut off the airflow to the engine.
If you are unsure of how to operate the machine, refer to your product manual.
How Long Should You Run A Karcher Pressure Washer?
You should limit the time you use the pressure washer. Like most machines, it is subject to wear and tear, which can cause parts to fail.
Regardless of the model, you should use your pressure washers for around three to five minutes only. Beyond this time, the washer can overheat. You can use the unit continuously, but allow breaks of 15-minute intervals.
The length of time you should use the washer also depends on its power source. Electric-powered washers can work continuously for one hour or more.
Gas-powered types can only work for 30 minutes. The running time depends on the machine's fuel tank capacity.
A washer's operating time also depends on the conditions of the machine. Using the washer outside when it is hot can cause it to overheat quickly.
Tips For Using A Karcher Pressure Washer

It is important that you know the correct way to use the pressure washer. Remember the tips below:
- Use a wide spray nozzle if cleaning wider spaces.
- Adjust the pressure based on the surface you are working on.
- Select the suitable attachment for the surface you are cleaning.
- Start the pressure washer slowly before adjusting it to a higher setting.
- Do not clean a large space all at once.
- Disconnect the washer from the power supply if you are not using it.
- For gas-powered models, remove the gas from the tank to avoid evaporation.
- Do not forget to clean the washer (including the hose and filter) after every use to prevent the clogging and accumulation of mold.
- Let the washer dry completely, then store it in a dry place.
- Use a Karcher pump guard to protect the machine from corrosion, freezing temperatures, and premature wear.
For further details, consult the product manual or a Karcher representative.
In Summary
A Karcher pressure washer will not turn on because of defective parts and internal components. The causes will vary depending on the type of washer you have.
There are simple steps to fix the issue, but you should ask for expert help if there are technical parts that need inspecting or replacing. You should also use and maintain the washer properly to prolong its life.
With a well-conditioned Karcher pressure washer, you can achieve a cleaner home.
Learn more about pressure washers from these posts:
9 Of The Best Pressure Washers For A Driveway
Should You Power Wash A Wooden Deck? [And How To]