Electrolux ESF 2435 dishwasher

Hello, My electrolux dishwasher started acting wierd the other day. I heard a strange humming sound and after 2min the sound was located and the dishwasher was the guilty one.

If i turn on the dishwasher it just start humming and nothing happens (does not take in any water or anything - just the humming sound).

I took it apart and:

-Checked for loose connections

-Checked the pumps for any junk

-Cheked the switch for the door

-Checked the switch that shuts down the dishwasher in case of leak

-Checked the solonoid for the water

I have located the humming noise to this thing :

It is located on the watertank but what is it? The noise stops if i take the wires of it.

Another problem that it looks like it has blown all the diodes control box

Any idea on what could be the problem? - is it just the control box thats fried or is something else that has fried it? The new price is 220USD for a new control box - if it needs replacement then i would be cheeper just to scrap the dish washer

Anyone got an idea?

Regards, Dennis