Joe: You need to phone any appliance repair shop and determine the "start up sequence" of your model of dishwasher. I'm not at all familiar with dish washers, but I'll explain what I mean with a clothes washer.
On a clothes washer, the start up sequence is typically as follows:
1.) electric power goes through the lid switch, through the temperature selector switch to the water mixing valve, and water starts to fill the wash basket.
2.) as the water level rises in the washer, air is trapped in a tube that goes up to an "air pressure switch". Once the water level in the washer is where it should be, the air pressure in that tube trips the air pressure switch, which diverts electrical power from the water mixing valve to the timer motor.
3.) the timer motor starts the wash cycle and the timer orchestrates the wash cycle sequence after that.
So, what you need to do is find out what the start up sequence is before the timer takes over, and one of the first things to always check is the lid switch or door switch because the power to the washer or dryer goes through that before anything else.
Also, dish washers use a solenoid hot water valve similar in design to washing machines. It could be that the dish washer has to partially fill with water before the timer motor starts. In that case, it could be the hot water solenoid that's not letting the water in to the appliance.
And, of course, a faulty timer motor or a faulty time is always a suspect, but timers are built fairly robust and are seldom the problem (relative to how often they're on the "short list" of suspects.