My Whirlpool dishwasher stopped working properly today. Some of the plates were clean to some degree while others were completely untouched, suggesting the arms were not moving. I tried running diagnostic mode, which ran fine, but I did not see any blinking lights. In addition, the manual does not have any discussion of what any error code would mean.
So, question is the following;
How can I find the error codes for this unit?
If I cannot find the error codes, how can I troubleshoot a spray arm that is not working properly?
I would not worry about error codes just yet.
I am assuming that you do have the tech sheet as you ran the diags.
First confirm that the arms are not moving.
If they are not then the most common causes are
Clogged filters reducing the water flow in the unit. Check/clean them.
Low water fill. The pump then sucks air and that reduces water flow. Most units fill to just under the heating element but I do not know on this unit. Often the pump is noisy as it is cavitating. An easy check is to add hot water after each fill in a cycle. Just be careful to not overfill it. Then if it washes OK odds are that the screen filter in the water valve is dirty.