Rear wiper and heated screen not working

[pug306driver]

yeah, estate with a lift up rear door/hatch............r/h/side speaker don't work........

more importantly need info on the heated rear window wires........one each side....one must be earth and the other the live feed....seen relay in there but that's for the wiper??

so which of the thickish heated rear window wires is the earth?? left or right and I presume the earth wire earths to the body close to the tailgate under the roof lining somewhere??

any help greatly appreciated......brilliant forum.