Bosch Dishwasher Error Code E05 — Water Switch / Float Switch Fault
What this means
The E05 error indicates a problem with the water switch Triac on the main control board, or a damaged float / defective float switch. The float switch is a safety device that prevents overfilling. When this circuit fails, the dishwasher cannot properly regulate water level.
Alternate codes: E5
Step-by-step fix
3 stepsCheck the float switch
Open the dishwasher door and locate the float assembly on the tub floor. Lift it up and down to ensure it moves freely.
Food debris or utensils can sometimes fall under the float and jam it in the up position.
Test the float switch
Unplug the dishwasher and use a multimeter to test the float switch for continuity. It should toggle between open and closed as the float moves.
If the switch shows no continuity change, replace it.
Inspect the control board
If the float switch tests fine, the water switch Triac on the control board has likely failed, requiring board replacement.
Look for visible burn marks or damage on the board near the relay area.
When to call a professional
If the float switch is functional but the error persists, the control board Triac has failed and professional repair is recommended.
Related error codes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
Learn more about our sourcesParts you may need
Links may earn us a commission at no extra cost to you. We only recommend parts relevant to this repair.