At first, I needed to find out what the E15 error code meant. After doing a search and learning what it meant, I removed the front of the dishwasher to examine the water situation. The basin was full, and I saw water across the whole base. As I looked more closely, I could see a steady drip from the valve assembly.
I knew I could find the name of the valve on AppliancePartsPros.com along with a video on how to replace it. I felt confident I could order the valve and replace it. I also ordered the fill hose to be safe. I thought the likelihood that the hose would not be reusable would be high.
Replacing the valve and hose took longer than the demonstration in the video, but it was my first time doing it, so I wasn't surprised.
After replacing the valve and hose, the dishwasher has been used several times, and my problem has not come back.