Kitchenaid KUDE48fx stops running

I have a new kitchenaid dishwasher - just out of warranty - KUDE48fx that runs for a few minutes and then shuts off. The green light was blinking in multiples of 4 and not working at all, but reset electronic pad with the 1,2,3,1,2,3,1,2,3 sequence and it will start a cycle now. However, it will only run for a few minutes now and then just turns off. There is usually water in the bottom of the DW, but will drain if the drain button is pushed. I lowered the upper rack the last time I tried to run the DW - the upper arm does sit well into the area at the back of the DW though. We did have a power outage recently so not sure if that did something either. Any thoughts/help would be greatly appreciated. Thanks!