How to Troubleshoot Error Code 1 on a Bosch Dishwasher

Meredith Jameson

Bosch brand appliances include items such as washers and dryers, ovens, ranges, microwaves, refrigerators, coffee makers, and dishwashers. Bosch dishwashers include concealed controls and visible control panels and are available in white, black and stainless steel varieties.

Bosch dishwashers are considered a high-end appliance and typically work well with standard care and maintenance. If an error code is displayed on the dishwasher, such as error code “1," troubleshooting the issue can help resolve it without the need for costly professional assistance. Error code 1 indicates a water sensor or filling error.


Always turn off power at the household fuse box or circuit breaker prior to performing troubleshooting on a dishwasher or other electrical appliance to prevent the possibility of electrocution.

  1. Turn the dishwasher off at the control panel and also at your central fuse box so that no power is going to the dishwasher. Ensure the water supply valve is turned on.

  2. Clean the filters, as obstructed or dirty filters can result in a water error. Unscrew the bottom spray arm and unscrew the filter cylinder. Remove any obstructions and rinse out the filters.

  3. Examine the waste water hose on the bottom of the dishwasher and ensure it is not blocked. Once the filters have been removed, scoop out any residual water. Using a spoon, lift off the pump cover and pull it up and off. Look inside the inner compartment and remove any obstacles. Place the cover back on top of the pump and press into place.

  4. Return the filters to their designated positions and screw the spray arm back into place in the bottom of the dishwasher.

  5. Ensure the water jets are not blocked by dishes or other items in the dishwasher. Look at the outlet nozzles on the spray arms and remove any possible debris or blockages.

  6. Turn the power on at the fuse box and on the dishwasher itself. Run a wash cycle to test the dishwasher and see if the error occurs again or if the above steps resolved the issue.

  7. Contact an authorized service technician if the above steps do not resolve the error code.