TL* THE CONTACT OWNS A 2005 BUICK LACROSSE. THE CONTACT STATED THAT THE MAIN WIRING HARNESS UNDER THE HOOD CAUGHT FIRE. THE CONTACT WAS ABLE TO EXTINGUISH THE FIRE AND TAKE THE VEHICLE TO THE DEALER. THE TECHNICIAN WAS UNABLE TO DIAGNOSE THE FAILURE. THE CONTACT STATED THAT THERE WAS NO WARNING PRIOR TO THE FIRE. THE FAILURE MILEAGE WAS UNKNOWN.