Dishwasher shows E12; often related to turbidity or water quality sensing issues on models with a turbidity sensor.

Safety first: Disconnect power before accessing the sump or side chamber.

Steps:

• Run a cleaning cycle: Use a dishwasher cleaner on the hottest program to remove grease and film that may cover the sensor window.
• Locate sensor: The turbidity sensor is usually mounted in the sump or a side chamber with a clear plastic window and a small connector.
• Clean sensor: Remove the sensor if possible and gently clean the optical window with a soft cloth and warm soapy water. Do not scratch the surface.
• Check wiring: Ensure the connector is secure and free of corrosion.

When to call a technician: If E12 persists after cleaning and the sensor tests faulty, replacement or control board diagnosis should be done by a professional.