Re: Bosch Dishwasher SHV46C (03UC/N) Tank not filling.

Hi
IT COULD BE THE FLOAT SWITCH ASSEMBLY>
PLEASE READ THE FOLLOWING VERY CAREFULLY AS WATER AND POWER DONT MIX WELL
Before testing the float switch, unplug the dishwasher or shut off the power at the fuse box or breaker panel to avoid an electrical shock hazard.

When the water in the tub lifts the float to a set point, the float switch is triggered and it shuts off the water inlet valve, stopping the flow of water. If the float switch is defective, the tub may overfill.If the float switch is obstructed or corroded it can prevent the tub from filling by holding the fill valve off !!so locate, check and clean.
To access the float switch remove the lower panel located beneath the door. The panel is usually held in place with two screws either above or below the panel. It may be necessary to first open the door to the dishwasher to reach the screws over the panel, then close the door to remove the panel.
Note the location of the float in the dishwasher's tub and you will find the float switch beneath it in the access area. The switch has two wires connected to it. Label the wires and connections so that you can properly reconnect them later. The wires are connected with slip on connectors. Firmly pull the connectors off of the terminals (do not pull on the wire itself). You may need to use a pair of needle-nose pliers to remove the connectors. Inspect the connectors and the terminals for corrosion. If either is corroded they should be cleaned or replaced.
Use a continuity tester or multitester to test for continuity. Set the multitester to the ohms setting X1. Touch one probe to each terminal. You should get a reading of either zero or infinity. With the probes still in place, depress the button or lever on the switch and the reading should change to the opposite extreme
if you have no voltage you have a bad timer.

However got this same information from a Bosch article...
Disconnect the power to the unit. Remove the lower access panels and check the tray under the dishwasher. You will probably find it is full of water. Use a towel or a sponge to remove the water. There is a float that will stop the operation of the unit and run the pump if water is in this tray. Test the unit. If there are no leaks, check the drain hose under the sink. THE DRAIN HOSE MUST RUN UP TO ABOVE THE TOP OF THE MACHINE THEN TO THE DRAIN. If the hose is not set up like this, water from the sink drain will flow into the dishwasher and overflow into the tray under it.
If there is no water in the pan under the dishwasher there may be a problem with the pressure switch at the side of the pump housing but the only way to know for sure is to do some electrical testing with a volt/ohm meter and the wiring diagram located within the appliance.
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