Kenmore dishwasher doesn’t pump out

This model pumps out standing water before the cycle starts. Lately, the pump will hum only until the door latch is opened and reclosed a couple times, then pump will run. The wash cycle seems pretty normal; fills, pumps and sprays, drains, but at the last pump-out, if I don’t keep an eye on it, the water isn’t pumped out, and at the end of the cycle, the dishes are still wet because the water is still in the bottom. (The element does heat up) Sound like an intermittent break in a wire somewhere? Or possibly something with the timer? Any ideas would be appreciated. Thanks.
D. W.