Reading in a CSV file in Javascript produces bad result with some characters

I have an Excel file of which I have exported to a CSV file with UTF-8 encoding with BOM and am trying to read in Javascript according to

// Note I am using adoptOpenJdk to import JAva packets in Js.
var myReader = new java.util.Scanner(myObj, "UTF-8");
var data = myReader.nextLine();

but it produces incorrect results for characters such as ÅÄÖ (swedish letters). ä becomes Σ and ö becomes ÷.

Anyone have an idea what may be causing this?