Plugged KitchenAid Dishwasher
 

My old KitchenAid Dishwasher, KDC-17, is plugged and water isn't draining out of it. The way to get it open isn't very intuitive and so I'd appreciate information on how to get to the filter or place that could be plugged and stopping it up. It sprays a little bit of water out when it goes through it's cycle but when the cycle is finished there is quite a bit of standing water left in the bottom.

It was in the house when I bought it and there was no owner's manual.

Thanks ahead of time.

Mike