hja 8630 dishwasher replacing the water inlet solenoid?

How do i change the water inlet solenoid on my HJA8630 DIPLOMAT dishwasher
I think its sticking as when i tap the water inlet hose fitting the dishwash will fill with water
I think its sticking and may just need cleaning but not sure
I took machine out of space and know how to remove the side panel nearest the inlet valve
What is next thing to do please