How to test pressure switch?

Keep getting F H code. Checked all hoses. everything looks good.
Could it be the pressure switch? And how could you tell?

Remove the small hose that goes to the tub from the pressure switch and blow in it, it should click. If ok, re-attatch to the tub, remove it from the pressure switch and blow in it. If clogged, force some vinegar down the hose with a tyrkey baster, should clear out any soap residue.

I replaced the control board water not going in ,this problem hapen before but this time didnt work