Car Locking itself

Hi all, have this problem with my Skoda Octavia 98 locking and unlocking itself among a few other things like the ventilation coming and going.

While trying to dismantle ventilation to check for blockages, I accidentally found where several wires earth.

Having touched them with a screwdriver, boom - all the doors locked. Did it again and they all unlocked.

Noticed one of the wires is badly green and oxidized and wondered if this could be the problem?

Does anyone know if you can simply clean the connection or if the wire would simply have to be replaced? If you can clean it, would it be appropriate to do it with a wire brush and some alcohol?