What is the third lead from 2011 panel for?

How about a 2011 LCD (A1286) fitting a mid 2010 MacBook Pro 15.4”?

I bought mint 2011 screen for my 2010 model and it fits perfectly but three press stud leads from LCD to Wi-Fi panel (2010 has two with a third lead emerging from beneath optical drive). What is the third lead from 2011 panel for?