Dishwasher KUDU03ftss0 Kitchen Aid Blown thermal fuse

[1bbroygb]

Hi

I have a Kitchen Aid KUDU03ftss0 dishwasher. The thermal fuse blew. What else should I check (and how) before I install a new fuse?

I took enough stuff apart so I could get to the drain pump. Their was A LOT of debris down there. Pistachio shells, plastic fork tines, etc. The "chopper" had also broken completely away from it's metal frame and was just laying there. So I am guessing debris passed through the drain pump and perhaps into the circulation pump? I'll be replacing the chopper and fuse and am thinking I should somehow check pumps before installing.

Also, is there a way to separate these arms? I mean remove the metal from the plastic? I tried gently prying up the plastic lip but it wouldn't budge at all.

Thank you!

[Vance R]

Remove the both pumps and inspect for debris. Make sure they turn freely by hand. Check the wire connectors for overheating. If the kit comes with splice wires - used the whole kit.

[1bbroygb]

Thanks!

I checked the drain pump and there was quite a bit of debris. The chopper blade had also separated from the metal disc. I replaced the thermal fuse and the chopper blade. Ran dishwasher (empty) on the "light China" setting with only the sump filter and chopper and it was fine. Then installed all the components and ran it empty on Heavy Duty with no dry. 

It blew the fuse again. When it stopped the heating element was hot and there were a couple of inches of water in the dishwasher. 

I'm guessing something is drawing too much current. Any advice on what to check next? 

[Vance R]

Usually the wash motor and heater element are on at the same time.  May want to check out heater and washer motor.

[1bbroygb]

Thanks! I checked the resistance of the heating element and it was 13 ohms (spec is 10 to 30). I also checked the resistance of the motor and it was 6 ohms (spec is 3 to 7 run winding and 6 to 10 aux). I checked these resistances at the wiring harnesses that plug into the control board after disconnecting them. Not at the units themselves.

I did notice that connect CON 2 and the area where it plugs into on the control board were both slightly burnt. Especially P8 which is in series with the door switch and thermal circuit breaker. A bad door switch couldn't cause the breaker to blow could it?

[1bbroygb]

Oh, I forgot to mention...I had replaced the thermal fuse and chopper blade. Cleaned everything out. I ran the unit on light China mode with the filter and sump cover in place. I then put it all back together and tried the have duty cycle with no dry. It stopped after about 45 minutes (blew thermal fuse). The heating element was hot, their was about 2 inches of water in the tub and it was hot too.

[1bbroygb]

The drain pump has a resistance of 23 ohms while the spec is 16 ohms. This was measured at the connector at the circuit board (disconnected). Is that enough difference to cause a problem?