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Parts for GE GSD3435F00WW Dishwasher - AppliancePartsPros.com

When you say it fill, how full does it get.
Most units fill to just under the heating element.

If it is not filling enough then it will not wash correctly.

If you think it is low you can add hot water to it just after each fill if it then washes then you know it is a fill problem.
Just be careful to not overfill it.

If it is low fill then the most likely culprit is the fill valve.
Shut off the water supply and remove the vavle.
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 cause a flood.
If the screen filter is clean then I would replace the valve.

If it is not a low fill problem then remove the kick plate and check the wash/rinse solenoid on the left hand side of the pump.
Check that it and the flapper valve arm are all the way up as this is the wash position.
If OK.
Remove the bottom spray arm and check that the chopper and filter on the pump are clean and do not have any debris such as twist ties etc. wrapped around the chopper.
Check that the spray hole in the arm are clean.
If OK
Remove the cover (back of the spray arm) and check in the sump to be sure it is clean.
Be careful when doing this as there is often broken glass in the sump.

I am assuming that when you say "spray is not working string enough to engage the soap dispenser." that you mean that that it is just not dissolving the detergent and that the dispenser does open during the cycle.
If the dispenser does not open then that is a different problem.