I just wrapped up the last leak on my Brasilia Portofino 1grp restoration/deep clean. Hopefully, your machine is like mine, only wider.
When I first got the machine I had symptoms similar to yours. I put the switch into position 1 (everything powered but heater) and was greeted by a very loud 60Hz hum, the "fill light" on and no auto-filling. I pushed the button on the front, the boiler filled and once it reached the fill probe the light turned off and the noise stopped. After tearing it down I discovered the fill solenoid was jammed.
I took the solenoid and brass manifold apart, gave it all a good soak and then put it all back together again. Before mounting it in the machine I plugged the solenoid into the wall through a light switch and 2A fuse. On the first actuation I got the horrible noise again and no clicking. Flipping the switch on an off in quick succession broke something free and the valve started clicking and the noise diminished dramatically. It's been fine ever since (about 2months).
I also reversed engineered the, trivial, wiring harness. The fill light is just in parallel with the 120VAC to the solenoid. When the light is on the solenoid is energized and water should be flowing.