About a week ago my dishwasher just stopped mid wash. The display went black and the buttons didn't respond. I was able to get into service mode, there was no error light lit up. I exited out and it seemed to be run through a cycle fine after that.
The next time I ran it it did it again. Blank display non responsive buttons. I pulled the kick plate and looked for any leaking water and it appears dry everywhere that I can see.
I entered service mode again and ran it through some tests.
First I tested the fill - no issues
Then I tested drain - no issues
Next I filled it back up and ran the circulation pump - no issues
Then I tested the heater - worked fine
Detergent module - no issues
After running through all the tests I reran them again. Now I'm getting issues.
Test fill - no problem
Circulation pump - no problem
Heater - I heard a couple clicks and it goes blank again. I dropped the control board down and it's blinking 7 times indicating the CSM is tripped.
(still full of water) Circulation pump - no issue
Drain pump - failed. CSM tripped again.
Test heater - failed again, CSM
Test circulation pump - all good
Test detergent module - all good
Test drain pump - Failed CSM
Unplugged the drain pump
test drain pump - seems ok
While still testing the drain pump I opened the door and plugged the pump back in and closed the door. Pump kicks on fine and drains the dishwasher.
Next I unplugged the heater from the board and try to test. The board blinks 4 times like the door is open, but does not fail.
I plugged it back in and retested it and it failed.
Then I checked the continuity of the heating element from the plug. Getting 16 ohms. Should be ok right?
Then I refilled with water and retested the drain pump and it failed again.
Unplug the drain pump and test it again - Now it's failing the CSM
I found training bulletin on the CSM and kind of followed it without replacing any parts. Link to CSM training document
I'm at a loss for what else to check. Every time it failed it was a CSM error on the board and it was randomly related to the heater or the drain pump. Is it the main board that needs replaced?