If your keypad is erratic or dead, you may need to replace the Control Panel. First, be sure this is the bad part. Your Whirlpool dishwasher should have technical instruction sheet stored behind the front kick panel. Follow the instructions to test the Control Board -- this involves removing and disconnecting the Control Panel. If the Control Board tests okay, the Control Panel is almost certainly the problem.
Installation is pretty easy, about 30 minutes. For my model, a T15 torx driver was the only tool needed. Search the web for details on how to remove the Control Panel on your dishwasher.