What does a dishwasher turbidity sensor do?

A dishwasher turbidity sensor measures the cloudiness or soil level of the wash water. This information helps the dishwasher determine how dirty the dishes are and adjust the wash cycle's length, temperature, and water usage to achieve optimal cleaning efficiency.

How do I know if my turbidity sensor is bad?

Common signs of a failing turbidity sensor include dishes not getting clean, wash cycles running excessively long or short, the dishwasher stopping unexpectedly, or displaying specific error codes related to water sensing. These symptoms suggest the sensor may not be accurately reporting water clarity.

Is it difficult to replace a dishwasher turbidity sensor?

Replacing a dishwasher turbidity sensor is generally considered a moderate difficulty repair. It often requires pulling the dishwasher out from its cabinet, disconnecting water lines, and accessing components underneath the appliance. Proper tools and caution are necessary.

LG Dishwasher Turbidity Sensor Replacement

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🏆 RECOMMENDED PART

Advice Appliance Parts Dishwasher Turbidity Sensor ABQ75742401, 4504039, PS12076725

✅ Part Number ABQ75742401, 4504039, PS12076725
✅ Model Number LDF5545BB/00, LDF5545BD/00, LDF5545ST/00, LDP6797BB/00, LDP6797BD/00, LDP6797ST/00, LDP6797WW/00, and more

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What the LDF5545BB does

The turbidity sensor detects the level of soil in the wash water. This information allows the dishwasher to adjust the wash cycle duration and water usage for optimal cleaning performance.

Symptoms when this part fails

Dishes not cleaning properly
Dishwasher cycles running too long
Dishwasher stopping mid-cycle
Error codes related to water quality
Dishwasher not starting

Compatibility

Fits the LG family. Specifically:

Any unit originally equipped with OEM part number(s): ABQ75742401, 4504039, PS12076725.
Check the model/rating plate inside your appliance and compare it against the fitment table on the product listing before ordering — this guide does not list specific compatible models because Amazon does not provide verified fitment data through this pipeline.

Also replaces: ABQ75742401, 4504039, PS12076725

Tools you'll need

Screwdriver
Pliers
Towel
Bucket
Gloves

Difficulty: Moderate · Time: 45-90 minutes

How to install the LDF5545BB, step by step

Disconnect power to the dishwasher at the breaker.
Turn off the water supply valve to the dishwasher.
Carefully pull the dishwasher out from its cabinet opening.
Locate the turbidity sensor, typically near the sump area underneath the unit.
Disconnect the wiring harness and any water connections from the old sensor.
Remove the old turbidity sensor from its housing.
Install the new turbidity sensor, ensuring all connections are secure.
Reconnect power and water, then test for leaks and proper function.

Related troubleshooting

If swapping this part doesn't fix the issue, check these next:

What is a Dishwasher Turbidity Sensor and How it Works