How can I diagnose the cause of my washing machine shocking me?
Putting  my proximity voltage detector within 40cm of the unit resulted in it  beeping (it usually needs to be within 1cm to detect anything.)


This usually means hot/neutral is reversed. There might be nothing wrong with the washer. Call an electrician first. And ground that outlet! Your machine's electronics will thank you.

(FWIW I use a non-contact voltage detector daily for diagnosing home appliances.)