wifes touran popped a fuse other day when I replaced it I noticed this wire any one know what it can be ? Car is completely standard apart from a towbar 

Looks like a very ammatuer modification-  I hope that it isn't just a spade connector jammed in to a fuse slot! 

 

Is it possible to pull out and see if anything stops working, It may be that whatever it was connected to was removed before you got the car.

I will have a look tomorrow will it be getting a live from there ? You think its save to pull out and see what stops working? 

Safe 

To be safe I would disconnect the battery first

It will be leading to the rear of the car to the towing electrics relay, I found a similar bodge & disconnected it as I could not see what it was doing, had forgotten all about it when I eventually towed & found the towing socket was dead, traced back the wiring all the way to the front of the car before it finally dawned on me.

 

Hopefully it will have an inline fuse but diconnect it & check & then make a proper connection.