Bosch Dishwasher Error Code Turbidity Sensor No Signal & Low Signal

This error means the dishwasher's control board is not receiving the expected pulse signals from the turbidity sensor, which monitors how dirty the wash water is. The control requires at least 50 pulses from the sensor within a 3-second window during operation. When that threshold is not met or no pulses are detected at all, the fault is triggered. The root cause is usually a dirty sensor, a wiring problem, or a failed sensor.

The turbidity sensor error does not typically represent a safety hazard such as a fire or flood risk. However, without a functioning sensor, the dishwasher cannot properly adjust its cycle based on water clarity, which can lead to poor cleaning results or a cycle that fails to complete. It is best to diagnose and resolve the issue before continued regular use.

A reset may temporarily clear the error code from the display, but if the underlying problem with the sensor, wiring, or control board has not been corrected, the fault will return during the next wash cycle. A reset is useful for confirming whether the error is intermittent or persistent, but it is not a repair. The root cause must be identified and addressed to permanently resolve the fault.

In some cases, yes. If the sensor lens is coated with grease or mineral scale, carefully cleaning it can restore the signal without any parts replacement. You should also check that the sensor's wire connector is fully seated and free of corrosion. If cleaning does not help and you are comfortable with basic appliance diagnostics, you can test the wiring for continuity and replace the sensor if it has failed.

If only cleaning is needed, the cost is minimal, essentially just your time. If the turbidity sensor itself needs replacement, parts typically range from $20 to $60 depending on the model, with professional labor adding $80 to $150 or more. If the control board is the cause, repair costs can range from $150 to $350 or higher for parts and labor combined.