Turbidity sensor fault — water clarity sensor not responding correctly
The F8E4 error on the Maytag MDB7959SKZ indicates turbidity sensor fault — water clarity sensor not responding correctly. This typically occurs due to heavy grease or film coating the turbidity sensor optics. A qualified technician can usually diagnose this in 20–30 min, but the steps below will help you understand the issue.
Safety Warning
This repair is recommended for certified technicians only. The diagnostic steps below can help you understand the issue before calling for service.
Common Causes of F8E4
- 1Heavy grease or film coating the turbidity sensor optics
- 2Turbidity sensor wiring connector loose or corroded
- 3Failed turbidity sensor component
- 4Control board input circuit for the sensor malfunctioning
How to Fix F8E4
- 1
Step 1
Cancel the cycle and turn off the dishwasher
- 2
Step 2
Locate the turbidity sensor at the bottom of the dishwasher tub near the drain filter
- 3
Step 3
Remove the filter assembly to access the sensor
- 4
Step 4
Wipe the sensor lens gently with a soft cloth dampened with white vinegar to remove grease or mineral film
- 5
Step 5
Reinstall the filter, run a hot water cycle with a dishwasher cleaner tablet, and test a normal cycle
- 6
Step 6
If F8E4 returns after cleaning, call a technician to test the sensor and wiring harness
Tools Needed
When to Call a Technician
Error returns after cleaning the sensor lens — the turbidity sensor or its wiring harness needs professional diagnosis
Frequently Asked Questions
Common questions about Maytag F8E4 error
The turbidity sensor in the Maytag MDB7959SKZ measures how dirty the wash water is by shining a light through it and measuring how much light is blocked by food particles. This information helps the wash cycle adapt its duration for load-dependent efficiency. When the sensor lens is coated with grease or the component fails, the F8E4 error is triggered.
The turbidity sensor only needs cleaning when it causes issues. Keeping the filter clean reduces the amount of food debris that can coat the sensor. Running a monthly hot water dishwasher cleaning cycle with a commercial dishwasher cleaner helps prevent grease buildup on the sensor lens as a part of routine maintenance.
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