How to resolve an E18 error on a Bosch dishwasher

If you’re seeing an E18 error on a Bosch dishwasher, it usually means the water level is too low or that water isn’t being pumped correctly. Fortunately, this is an easy issue to resolve in just a few minutes.

If you find out that you need any replacement parts for your Bosch dishwasher while you’re troubleshooting, you can enter your model number at AppliancePartsPros.com to order them. Most orders arrive in just two business days, and we have thousands of free guides to show you how to install your new parts.

Disclaimer: The error code information provided in this article may not apply to your specific appliance model. While we strive to offer helpful advice for DIY appliance repairs, variations in models and configurations can lead to differences in troubleshooting steps, error codes and part replacements. For the most accurate guidance, we strongly recommend consulting the technical sheet for your specific appliance model.

Safety tips

• Always power off and unplug your appliance or switch off the circuit breaker before you attempt any maintenance or replacement work. This keeps you safe by preventing any risk of electric shock.
• If the appliance has recently been used, give it plenty of time to cool down before working on it.
• Turn off the water supply at the outlet before beginning repairs. Keep towels ready to catch any residual water in the system when removing parts.
• Take your time while working to prevent accidents and personal injuries. Rushing is the enemy of precision.
• Work in a well-lit area so you can see and access appliance parts.
• Keep your workspace free of clutter and other obstacles. Keep children and pets away from the work area.
• Never work on internal parts with wet hands. Make sure the work area is completely dry.
• Check the user manual to see if there are specific installation or safety instructions related to your appliance or replacement part.
• Be gentle when handling or removing parts. Excessive force might damage the appliance or cause personal injury.
• Wear insulated work gloves to protect your hands from sharp metal parts and debris.
• When working with wires, avoid touching any exposed wires or terminals. If you need to touch a wire, use a non-conductive tool or wear insulating gloves to prevent electrical shock.
• Always take photos or make a note of wiring terminals or other connections before disconnecting them to make reassembly easier.
• Don’t test live voltage with a multimeter if you’re unfamiliar with how to prevent short-circuiting.

Read more: How to level a dishwasher

How to troubleshoot the E18 error code

Roll up your sleeves and tackle the E18 fault code head-on by following these troubleshooting steps.

Step 1: Check the water supply

A low water flow rate can prevent the dishwasher from getting enough water, which can trigger the E18 error.

1. Unplug the dishwasher.
2. Find the water shut-off valve that’s connected to the dishwasher. It’s typically located under the sink. Make sure the valve is open and allowing water to flow to the dishwasher.
3. The recommended water flow rate is around 10 liters per minute (l/min). To measure the flow rate, you use a measuring container and a stopwatch. Place the container under the faucet that’s connected to the dishwasher and turn on the water. Measure the time it takes to fill the container to the 10-liter mark. If it takes longer than a minute, the water supply may be insufficient.
4. Reconnect everything and restore power to the dishwasher.
5. Run a test cycle to see if the error code has been resolved. If it hasn’t, move on to the next step.

Step 2: Check the water connection filters

The filters in the water connection of the supply or AquaStop hose are designed to prevent debris or sediment from entering the dishwasher and causing issues with water flow. When these filters become clogged, it can restrict the water flow and trigger the error code.

1. Unplug the dishwasher from the power outlet.
2. Find the water tap that supplies water to the dishwasher. Rotate the handle or lever to turn off the water flow.
3. Find the water connection on the back of the dishwasher. Use a wrench or pliers to carefully unscrew the water connection and separate it from the dishwasher.
4. Find the filter inside. Depending on your model, it may be located at the end of the supply hose or within the water connection itself. Gently remove the filter from its position.
5. Rinse the filter under running water to remove any dirt, debris, or sediment that may have accumulated in it. Use a soft brush or toothbrush to scrub away stubborn residue if needed. If the filter is damaged, replace it with a new one.
6. Once the filter is clean, carefully place it back into its original position in the supply hose or water connection.
7. Align the water connection with the opening on the dishwasher and screw it back on. Use a wrench or pliers to tighten it if needed.
8. Turn on the water supply and check for any leaks around the connection.
9. Plug the dishwasher back in and run a test cycle to see if the error code has been resolved.

Step 3: Check the inlet hose

The inlet hose brings water into the dishwasher from the main water supply. If this hose is obstructed, bent, or damaged, it can restrict the water flow and trigger the E18 error code.

1. Find the inlet hose, which is usually located at the back of the dishwasher and is connected to the water supply valve. It’s typically a flexible rubber or braided hose.
2. Turn off the water supply to the dishwasher.
3. Disconnect the water supply line from the dishwasher and the shut-off valve.
4. Inspect the line for any clogs, debris or damage. If you find any, clean the line thoroughly or replace it.
5. Carefully examine the entire length of the inlet hose. Look for kinks, bends, or visible damage. Check for any sharp bends or twists that may restrict the water flow. If you notice any kinks or bends in the hose, gently straighten them out.
6. Once you’ve checked and made any necessary adjustments or replacements, reconnect the inlet hose to the water supply valve.
7. Turn on the water supply and restore power to the dishwasher. Run a test cycle to see if the error code has been resolved. If it hasn’t, and there’s not a normal amount of water in the tub when it fills, replace the inlet valve.

Read more: How to clean dishwasher spray arms

Additional information

Thank you for reading! We hope this guide helped you get your Bosch dishwasher working again.

If you have any other appliance repair needs or projects, don’t hesitate to explore our other troubleshooting guides and videos.

If you need replacement parts or some extra help with ordering them, grab your model number and head over to AppliancePartsPros.com, where you can chat with a pro, read our DIY blog and more.

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