Bonnet earth strap

Hello

I changed the foam plenum air intake filter today and while i was moving the three parts of the grill, the small plastic grill on the right (as you look at it from the front of the car),the one that has a long rubber boot with an earth wirth that bolts to the inside of the bonnet, just came away from the rest of the wire that was behind the grill. the wire itself was in bad shape and it had corrosion on it, i suspect it had overheated. I've connected it back up, but does anyone know what this earth wire is for? I don't think it is for the heated screen, as i saw two wires that round each side of the middle wiper spindle.

Thanks Kev

I know no one has answered, but i have managed to attach a picture, if that helps.

Thanks Kev

i think its just a static earth incase the bonnet dosnt earth through the hinges.