Product review (5 stars): SIMPLE cheap fix for dishwaster...VERY much a replace yourself kind of job!
Our dishwasher simply wasn't cleaning, and we noticed our heating element was broken in half.  Although we did have to remove the dishwasher from the cabinet and undo some wires, it was really easy to do.  There is a video on YouTube that walks you through this process step by step.

It is worth the few dollars to try replacing this (and making sure that your dishwasher is hooked up to the HOT water pipe) before calling a service tech.  We have almost no experience working on this kind of stuff and my husband and I did it with no problem.