Start with filling...
Is there any water going into the tank? Has someone mistakenly turned off the water valve to the dishwasher? Maybe you installed a new kitchen faucet and turned off the dishwasher supply as well but forgot to reopen it?
The Model number would help. Sounds like it is a KDI-19 but we like to be sure.
If there is some but not much water going in, then the water valve screen is most likely clogged up with debris and should be cleaned or the valve replaced.
The detergent dispenser doors will NOT open if there is not enough water in the tank for the pump to pump around. The drag on the motor caused by the water allows the motor to draw the correct amperage which is directed thru the detergent door bimetal heaters causing them to bend and release the doors. Once they open, the timer redirects the current directly to the pump motor. This happens for each of the detergent doors as well as the rinse aid dispenser later on in the cycle.
Hope this is a helpful start for you. If not, we are all here to helpyou solve the problem.