Whirlpool Not Draining

Just noticed that my Whirlpool DU912PFGB1 is not draining. The only thing I have checked so far is the drain hose to my disposal looks clear. I have to drain the water out to check anything else.

Any help on what to check on first? I am trying to find the repair manual on line but have not found it yet. I have never repaired a dishwasher yet so any help would be great.

Thanks, Dennis.