I recently changed my brake pads and took some pictures. It doesn't show the sensor wire route but i will still post them anyway, maybe it helps give you an idea.
The sensor is a simple wire loop, when it brakes (apparently at 4mm pad thickness) it triggers the track driving warning only. At this point the car is ok to drive on the road. The "your pads are done" warning is a mechanical metal tab that would scrape over the disk and make an annoying noise when the pads are at about 2mm thickness. Pretty standard on most asian cars I've driven.
The sensor wire is connected to the inner pad of the rh side brakes. The wire goes from there through the little opening on the front side of the brake caliper and in to the sensor connector mounted on the knuckle.
When i pulled the brake pads out, i cut off the wire opened up the two leads, soldered them together and put some shrink wrap on them for protection and tucked it in somewhere on the harness. You can see me holding up the ready to tuck lead in my hand on one of the pictures. I could have cut it shorter though, i don't know why i left that much of wire now.
Mine was totally stuck to the brake pad btw. Maybe it welded itself due to heat, maybe it comes pre assembled like this. You will find out when you remove yours.
