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Replacement parts for GE GHDA480N00WW | AppliancePartsPros.com

Check to be sure the foat is not sticking in the up position.
This flood switch disconnects power to the water valve if it is not activated.

Check that the water valve is getting power when it should with a meter (120 volts).
If it is getting power and not opening then it needs replacing.

If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.

There is a good STICKY at the start of this forum about it's use.

Front right hand side in the tub.
Switch is Item 3089 in the "Body parts" section

found the float on the front left side.
OOPS! Must have had my head up my you know what or I just need another cup of coffee

Anyway, my question is regarding the testing of the water valve using a voltmeter. I've read the Sticky on voltmeter use so if I disconnect the power and check the two contact points on the water valve, should the voltmeter be showing 0 or infinity.
Should be reading some resistance, am not sure how much.
It will not be 0 as this would be a short and would blow your breaker.
If it is infinity then the coil in the valve is open and it needs replacing.
Use a high meter scale to check for infinity as a the coil may be outside the range on a low scale and show infinity when in actuality there is resistance

Sorry, I'm a total electric newb.
Not to worry, everyone was a newb at one time

From what you said, if it showing "0" and not getting water I should replace the valve. Is that correct?
Just check it for resistance.
Note that the coil in the valve may be OK and the valve still will not open. So if you get a resistance, reattach the wires to the solenoid, set your meter to AC volts on a 200 volt scale and start a cycle. If the valve gets 120 volts and does not open then it is the valve for sure.