Chosen Solution
My 4 yr old Whirlpool Gold WDF750SAYW3 dishwasher is really frustrating me. I’ve replaced the door latch, because it seemed when it started acting up, that if I “twisted” the door just right, it would start running again. It worked fine for 3 loads after the new door latch, then back to not completing anything beyond filling and dumping the soap. It will always drain by the way. So I replaced the circuit board. Ha. I thought it worked fine for one load, but the last two tries it hasn’t actually Washed the dishes, and the dry function is not working at all. What Else Could It Be???? I’m already down about $125 - much more and I should have just bought a new dishwasher.
Error code 7-1 is your washer is getting no heat, and depending on the cycle selection it may time out before the water gets hot enough to start washing. Things to try: 1.) run the hot water in the sink before turning on the dishwasher, 2.) bump up the hot water thermostat to 120 degrees, or 3.) run in at the Eco setting as this requires less hot water. If none of the above works, then test the heating circuit:
Measure resistance between the connections of the heater element. Should measure between 8 and 30 ohms. If not, replace. You can buy a new one here: https://www.searspartsdirect.com/part-nu… Next, measure continuity in the high-limit thermostat. You should have continuity. If it tests open, then replace it. You can buy a new one here: https://www.searspartsdirect.com/part-nu… Now, the door switch circuit is also part of the heater L1 Relay, so your twisting the door may be on to something. Here is a diagram of the door switch circuit:
As you can see all of those relays are on the control board, but you’ve already replaced that, so I wouldn’t focus there. However, you can test between P9-6 and P9-5 and see if you get continuity when the door switch is closed, and an open circuit when the door switch is open. I would take this measurement a few times to see if there is an intermittent problem (e.g. like door twisting). I would also check the wires connectors between the door switch and the control board for damage. The other thing is the water fill circuit and the fill valves. I would check the overfill float switch is working correctly, and that the fill valves are not clogged. What could be happening is it is filling up with water, but too slowly and is timing out. I would expect an error code if this happened, so I would focus on the above first, but just in case here is the diagram for the fill circuit:
