problem with menu_open *** HELP ***

[Mr.Joker]

Hi guys

I have a problem with a Icon Menu_open.gif :

This icon is disappearance from my Navbar and I can't open neither Menu!

I try to revert Navbar template but it's don't see...Where can I modify to restore this icon?
From which file or template is loaded this icon, please?

I have vbulletin_menu.js

Tanks