Turbidity or Soil Sensor is used in many dishwashers. It is used to monitor the soil level and automatically adjust the amount of energy and water required to clean the dishes. The turbidity sensor shines light through a small sampling of dishwater measuring sediment content and adjusts the dishwasher's cycle time and functions accordingly. Turbidity sensor optimizes the load and cycle; therefore, saves energy and water and it also helps to automate the cycle setting.

One of the main problems caused by faulty turbidity sensor is the extended wash time.