Hi, Im Daniel and welcome to Just Answer. Sorry to hear you are having trouble with your hood, Hopefully i can help you on this.
You may get an offer for a phone request, Now im afraid i dont do them as i only do the online chat so if you dont want the phone request then just ignore it.
If the start button is broken then it just needs a new one.
These are prone for breaking on these Whirlpool washers as ive replaced loads of them for this fault.
To replace the start button you need to pull the washer out and remove the top panel and unplug the washer.
Then remove the soap drawer and undo the screws behind there.
Then remove the screws on the top of the control panel.
Then look behind the control panel on the far right and theres a plastic tab there.
You need to push this tab and at the same time pull the far right of the control panel out and you can remove it from there.
Then remove the control board and you can access the buttons from there.
You can swap it over from there.
Try that as ths usually cures the issue here.