KitchenAid dishwasher not heating water hot enough

[SIZE=3]We have a KitchenAid dishwasher (Model KUDA23SBWH0) and we like it however we are noticing spots on the glasses – we use jet dry. So we ran it and waited until the water was heated and it started up. The water does not hear to 128 degrees – so the water is not getting hot enough – you can put your hand in it without discomfort. We are assuming that it would be the heating element that would need to be replaced and just want to find out if that would be the correct assumption or if we need to check anything else. We see that in the parts list there are temp probes (which are discontinued). We are hoping someone could give us advice on this. We do not want to get a new dishwasher and would like to fix this one. Thank you in advance for your assistance [/SIZE]