My dishwasher isn't working like it's supposed to. Everything seems to be working fine, but then after the machine stops, I open the door and see that my glasses and plates are suspiciously grimy. When I expose the detergent cup, I see this:
Clearly the detergent (I've tried a couple types) isn't flowing out from its cup like it should be.
What's the fix here?
The cover of the detergent cup is not opening when its supposed to. If you need to expose the cup to investigate, it is not opening at all. The spring loaded cover is held closed over the detergent by a little catch. There is a solenoid in the door that pulls on the catch, letting the cover spring open. This happens at the start of the main wash cycle. The cover is not that water tight, water normally leaks in, causing the detergent to start caking.
Once the cover opens, exposing the detergent to the main water jets, the minor caking is not an issue, all the detergent gets washed out. When the cover doesn't open, the main water jets cannot wash out the damp detergent.
The reason the cover does not open usually is the solenoid fails and needs replacement, though it's possible something else is at fault. Faulty wiring, faulty relay or triac on the control board, some sort of timer issue, etc.
If you can locate the solenoid, try measuring the resistance of the coil with the wiring removed. If it's either hardly any or nearly infinite, the coil is at fault. Solenoids can fail for other reasons, so reasonable resistance does not mean it is not at fault.
Unless you can observe something out of place, like a broken wire, that is probably the extent of DIY troubleshooting.
bcworkzs answer provides the correct solution, the cover isn't opening, and goes on to explain why that might be:
The reason the cover does not open usually is the solenoid fails and needs replacement, though it's possible something else is at fault. Faulty wiring, faulty relay or triac on the control board, some sort of timer issue, etc.
Just in case somebody else comes here with a caking problem, I would like to add another possible cause of the cover not opening:
It might be some of the content of the dishwasher that is blocking it, so it cannot open. This has happened to me a few times (most often when washing large items). So if you are having this problem sometimes, but not always, check that you haven't blocked the space where it is supposed to open into. This happens more often if the cover is hinged instead of sliding.
The reason it does not open is because when the door flips open it hits the dish rack, at least that's what happens to my Kitchenaid.
Try a liquid detergent most major supermarkets have their own branded product. If you must use a tablet make sure the dispenser is dry first then give it a short spray of silicon furniture polish before inserting the tablet.
