Kitchen Aid Dishwasher

Soap dispenser doors do not open during the wash cycle. It is constant for the prewash and intermittent for the main wash. What parts do I need and how do I repair it?

I would start with the Bi-Metal’s on the det. cups. (if you can find them) This unit is getting OLD!!! Also, It will work just fine if you fill only 1 cup and DON’T close the cover.