THE LARGE (1.5IN.) BUNDLE OF WIRES THAT GOES FROM THE BATTERY/FUSE BOX TO THE STARTER/OTHER PLACES...GOES THROUGH A CUTOUT IN THE BOTTOM/FRONT OF THE VEHICLE THIS BUNDLE RUBS WITH VIBRATION UNTILL THE INSULATION IS GONE. SHORT CAUSES THE FIRE. MY BROTHER'S VAN IS BUILT THE SAME WAY.