whirlpool generation 2000+

Anyone know what may be causing this fault and how to fix it? I have a Whirlpool Generation 2000+ G2P DWI Dishwasher that was in the house when we moved in in 2012 (i.e. Don't know how old it is), and it has recently started beeping at the end/mid way through the cycle and ends up on the rinse...