Brand New Whirlpool GU2500XTP Dishwasher will not complete cycle

I purchased our Whirlpool dishwasher GU2500XTP from Appliance Land in Martinez, GA. They installed it on Thursday, December 30th. That night we loaded the dishwasher and push the start button. It started going through it's normal cycles. About 1 hour later or so, I came to see what it was doing. The status "cleaning" light was blinking. I checked the troubleshoot section and it said I have a major problem. So next morning, I call Appliance Land and explained what happen and thinking they would simple swap out the dishwasher. They sent out the people who installed it and simple checked the hook up they did. They said there work was correct and the problem was in the brand new dishwasher. So while the guy was still there, I called and spoke with the manager. He told me it was out of his hands that i would have to call Whirlpool for service. He would not swap it out even though that just installed it the prior day.