how do i replace the switch? another site said to check the fuse. where is that?

i took off four star screws on the top and the four on the metal panel on the back.

i unplugged some white plastic thing right behind the button. when i plugged it back in and then plugged the whole machine back in, it worked.

i had a tech come out on this in the fall. he just ran like a magnet or something over the switch to reset it. then he charged me. a lot.

it says there is a simple fuse back there but i did not see anything that looks like a fuse. just a bunch of black boxes with amps and stuff on them. they don't seem to be able to be removed though.