Below is what comes up when I search for your unit.
Replacement parts for GSD500D models | AppliancePartsPros.com

Could it be a 03BW instead of 038W.
I am going to assume that it is and I used 03BH as it is the closest to 03BW.

There are a couple things that can cause no water.
1. Remove the kick plate and check that the float switch (Item 490 in Section 2) is being activated. Sometimes the float can hang in the up position.
This is a safety switch and kills power to the water valve if the unit over fills, preventing a flood.

2. Check to see if the fill valve (shows as Item 1209 but is listed as 783 in Section 2) gets voltage (120 volts) when it should be filling.

If there is 120 volts then remove the valve from the unit and check/clean the screen filter on the input side of the valve. Do not permanently remove it as it is there to keep crud out of the valve which could hold it open and cause a flood.
If there is 120 and the screen is clean and the water supply OK then replace the valve.

If there is no 120 volts, check across the float switch. If you have 120 here then the switch is probably no good. This can be confirmed by removing power from the unit and one wire from the switch and checking it using ohms. Should be 0 ohms when activated.
If 0 volts across the switch check the valve/switch combo (they are wired in series). If there is no voltage there then probably you have a bad connection/wire or the timer is no good.