you can have conflict issue if you using .tab_map class somewhere. add id to your li tag
html
<li id="map_canvas_tab" class="tab tab_map"><a href="#sp_tab2"><img id="tab_map_icon" src="../Icons/property_map_icon_G.png" />Map</a></li>
jquery
$("#map_canvas_tab").on("click", function () {
alert("tab no 2 is clicked....");
});