how to reset scroll position in a div using javascript

It is easy

 <div id="test" style="height:150px; width:600px;overflow-y:auto;background-color:gray;">
     <div style="width:150px;height:500px; background-color:green;"></div>
 </div>

document.getElementById('test').scrollTop =0;

Without seeing code, i can just guess. If you want to reset the scroll position you can simply use

window.scrollTo(0,0); 

add this code to your each tab click functions so that when ever you click any tab, it resets to top.

If you have any specific div that has overflow property

var myDiv = document.getElementById('specificDiv');
myDiv.scrollTop = 0;