How to Troubleshoot & Replace Whirlpool AP6023867 / WPW10705575 Turbidity Sensor

My wife said we have a problem with our dishwasher (Whirlpool WDT920SADE2). The dishes were not getting clean, and the soap dispenser opened, but soap was still dribbled down the inside of the door and on the silverware caddy. I'm not the handiest guy; it took me several days to go through the trouble-shooting process, watching multiple videos and trying different things. My initial guess was that the soap dispenser was opening too late. (This turned out to be wrong.) I started off by running a full (3-hour) and quick (1-hour) cycle, stopping it occasionally to check what was occurring inside. I realized that the water was room temperature and the heating element never activated. I took the kick panel off and found the instructions for the installer, which explained how to activate a diagnostic cycle (Press any three keys in the order 123-123-123). I had to read the instructions about 10 times before it started to make sense to me - the test intervals are numbered backwards, from 26 down to 1; very counter-intuitive! Anyway, the test showed function F7 (heating), error E1 (no heat). The notes for F7-E1 said that either the heating element was bad or their was a circuit problem where the heating element was not being turned on. They also said that in case of a heating problem, the Control Unit would disable the heater but keep running the full cycle. We always run the hot water at the sink before we start the dishwasher. This explained why it took us a while to realize there was an issue with the dishwasher, because the cycle would complete normally. It also explained why the soap was still there at the end of the cycle - the water was too cold to dissolve it. To solve this, I first watched some youtube videos on removing/testing the heating element. It took me a long time to remove the heating element, mainly because it was really hard to get my electric wires disconnected so I could pull the dishwasher out from the cabinet. My wiring was placed more awkwardly than the wiring in the demonstrations. Murphy strikes again! Anyway, after testing, the heating element was just fine. Next, I looked at all the wiring from the control unit to the various sensors, because some people had broken wires. Mine all looked brand new. I was a bit at a loss at this point, since everything checked out ok. I knew that somehow the signal was not being sent to the heating element to turn it on. Grasping at straws, I watched an AppliancePartsPros video on the turbidity sensor and decided to take it out to look at it. It was really easy to remove; in hindsight, I didn't even need to disconnect the wiring to get to it on my dishwasher. It was very dirty and looked like it might be compromised internally, so I decided to order the part on Friday around noon. I was thinking, if this doesn't work, I'll have to either order a new control unit (based on the notes in the install guide for F7-E1) or call in an expert, depending on the cost of the control unit. The new turbidity sensor arrived the very next day - amazing service! I had told my family I wouldn't be able to continue work on the dishwasher till Monday, but I got it installed in record time and ran the test cycle Saturday afternoon. Voila - I now had heat! One weird thing; the F7-E1 kept showing up. I thought it would auto-clear, but when I ran another diagnostic cycle it was still there. I finally figured out that I had to press the HI-TEMP button during the test interval right after the 4 customer codes are shown. (I think it's interval 22). You have to be quick because the interval is only 6 seconds long. Anyway, I got my dishwasher all to put back together and it's working great now, so the issue was definitely the turbidity sensor. Kudos to AppliancePartsPros for their great step-by-step videos and their quick parts delivery! 

I’d like to start by saying thanks to David F from Austin Tx for his post. I had replaced the heating element and the other part recommended to no avail. My dishwasher (whirlpool WDF770SAFZ0) started not drying the dishes to start and over time I noticed that the countertop no longer got hot and the dishes started coming out dirty and/or with a slick film on them. The dishwasher cleaner tab also only half dissolved. I was going of of my mind as to what the issue was because I replaced everything those problems call for. Mind you my dishwasher is only 3 years old. When I read David F’s post it was like he was writing exactly about everything going on with my own dishwasher. If you look at the turbidity sensor information though, it doesn’t state this part effects the temperature issues with your dishwasher- I mean why would it?? I ordered the part and eureka after replacing that my dishwasher cleaned perfectly AND dried completely!!! I also noticed that the countertop was warm again AND that over time the sounds my dishwasher made to indicate it was cleaning had stopped so running it with all the sounds back to normal I realized just how long it had been since it was an issue. Couple things of note: 1. my heating element was actually fine when I tested it but I replaced it anyway because that was the most obvious. Much more complicated job. In fact everything replaced was more complicated than the sensor so if you have the same issues as I had I’d recommend actually trying the sensor first because you don’t have to turn the dishwasher on its front you can just reach under. Be aware water will come out when you unscrew the sensor so have towels ready. 2. After replacing the sensor I ran a full diagnostic again. Not sure if it was necessary but not a bad idea just to have the system reset itself. 3. The diagnostic process is VERY bizarre and there are several variations out there for Whirlpool. None of the manuals (even the installation manual) will not tell you which version is your dishwasher’s sequence but I figured out for my model it’s the 1,2,3…1,2,3….1,2,3 process followed by number two. Which buttons are what is the mystery…if you have my model it’s 1=heated dry, 2=hight temp wash, 3=target clean. You press them in sequence quickly one after the other and do it three times followed by pressing and HOLDING #2 (high temp wash) until all the lights start flashing then release the #2 button and it will begin. The process takes about 20 minutes for my dishwasher model and there is no warning or alarm at the end so stay close because once the process is complete it will simply flash in the display your F and E code twice and then shut off. Hope this is helpful for people out there….it was tedious for me to figure out what was wrong since the error didn’t match up with the recommended part replacements or maintenance suggestions (like cleaning out the filter). Good luck! 

We ordered the parts and we fixed the problem. Your web site was very helpful. 

After thinking about the problem, and not wanting to pull dishwasher out of the cabinet again. I examined the drain hose at the sink, and discovered it clogged. After removing the clog, and blowing on the hose, water started to drain. I am a happy camper now. Parts will be stored for next time. 

The turbidity sensor fixed the long run time. Easy to replace thanks to your helpful video. Heater Assembly fixed the drying problem. Another easy fix thanks to your helpful video's. And last but least the water level switch. All three were faulted during the error code test. Now the dishwasher runs like new again. Thank You. 

Bought a new sump/motor assembly to make it an easy swap out instead of buying just the motor. Assembly also came with a new diverter motor so I won't have to worry about having to go back in there if that failed. I also purchased new turbidity sensor and drain pump (which I found out had a small leak in addition to starting to fail) since I was already in there. The machine works like it's brand new now. 

Performed diagnostic tests. Had code for no heat. I performed a continuity check on the element and found it to be bad. I replaced the Heating Element per the video directions they provided on their website. I also replaced the Hi-Limit Thermostat since I was in that area already. The dishwasher is repaired for a fraction of the cost of what I would have paid a repair person to do the work. 

We did the diagnostic check and it was indicating 7-1 heating element. But they were out of stock. I kept reading and a reviewer had the same issue but he found the heating element was fine it was actually the sensor that needed to be replaced. It was in stock and inexpensive so we ordered it. The repair was easy following the video online. Our dishwasher is working again. Great service. 

Given the location and number of connections that had to be switched out and since I had to disconnect the electrical to install the new harness, I decided it would be easier to just pull the unit out and tilt it over so I could see what I was doing. So I disconnected the water supply and drain lines then the electric, two mounting screws and pulled the unit. You also have to remove the front panel to acces wiring to the control panel etc. Once that’s done it’s a matter of remove and replace the color coded plugs and ground wires and then reinstall. The tech that diagnosed the problem suggested leaving the unit in place and pulling the motor up inside and proceed from there. Given how many plugs etc that are under the unit I believe that would have been an exercise in frustation. 

Looked up the problem online, found a video about replacing the turbidity señor at AppliancePartsPros. Ordered the part and installed it per the video. Went very smoothly. Thanks for the video!