Maytag dishwasher MDB7760AWS0 won't do anything, already changed control board and diagnosed thermal fuse.

[TTDave]

My dishwasher recently stopped working.  There have always been lights on the control panel on top of the door and now there is nothing.  I verified power at the dishwasher connection and at L1 of the control board.  I read that if the control panel on top of the door is bad, unplug it from the control board and the dishwasher should complete a fill and drain cycle, if not, the control board is bad.  I did this and nothing so, I assumed the control board was bad.  I replaced the control board and still nothing with the control panel unhooked.  I checked for continuity across the thermal fuse, it is good, and also checked for power at the board, there is 122 VAC on the L1 pin.  Any and all help would be appreciated!   

[Vance R]

Since your post didn't indicate test points used to measure voltage. Did you use P2 (w/bl wire) for neutral to P6 (bk/w wire) for line? Then with the door closed P4 (w/v wire) for neutral to P8 ( t wire) line there should be 120 vac.

[TTDave]

On 5/28/2021 at 11:48 PM, Vance R said:

Since your post didn't indicate test points used to measure voltage. Did you use P2 (w/bl wire) for neutral to P6 (bk/w wire) for line? Then with the door closed P4 (w/v wire) for neutral to P8 ( t wire) line there should be 120 vac.

Vance,

Thank you for the response, I should have been more clear.  I did check between P2 and P6 and had 122 vac, then, oddly enough, the machine mysteriously worked for two loads (probably the reason that I never saw this response from you) then it stopped again.  So I took it apart again and was trying to test as you suggested and now I do not show power between the two.  I do, however, show power on one side of the thermal fuse and not the other.  When I unhooked and tested for continuity across the thermal fuse, it is intermittent and almost seems as it has continuity but can't handle any current at all.  Is this a common way for these to fail?

[Vance R]

1 hour ago, TTDave said:

Is this a common way for these to fail?

Common symptom of a loose connection.

[TTDave]

18 hours ago, Vance R said:

Common symptom of a loose connection.

There is just Fluke 87 multimeter to each terminal of the thermal switch.  

[TTDave]

Just now, TTDave said:

There is just Fluke 87 multimeter to each terminal of the thermal switch.  

I am ordering another thermal switch and hoping that is the issue. Operated fine with a jumper in place but I am a little scared to run a whole cycle like that in case there is another problem somewhere.

[TTDave]

So the thermal fuse did not help the issue, it made it most of the way through a cycle and then stopped.  The dishwasher had a very hot smell to it as it was going through the cycle, smelled electrically hot.  could there be a relay stuck somewhere in it or something like that?

[Vance R]

9 hours ago, TTDave said:

could there be a relay stuck somewhere in it or something like that?

Did you install the tco kit?

[TTDave]

I'm sorry it took me so long to get back to you, I installed the thermal fuse and wires as the kit suggested and replaced the control board, it ran through about half of a cycle and the thermal fuse failed again.  I had heard through the grapevine that there was a service bulletin on them that required the black and the black with white stripe wire to be replaced for the whole machine and this would fix it. My girlfriend and I got fed up with washing dishes by hand and bought another dishwasher and I gave this one to a friend.  He is going to change the wires and I will update you as to the outcome of that change.

[Trossbarco]

Does your machine have "soil sense" as a wash option. I have seen OWI sensors cause intermittent no runs and or short/long cycles. A broken harness would not cause the thermal fuse to pop it would reduce amperage if there was a bad connection.