fuse block wiring '90 240sx

[xekushnr]

Tried searching, didnt find s***.

My reverse lights havent worked since I bought the car. I'm only getting 0.8 volts at the back up light fuse, so I need to look before that. The problem is that my wiring diagram doesnt give any info about the wiring before the fuse block. What color is the wire that runs to that bottom right 10A fuse and where does it come from?

[xekushnr]

Nevermind, I just found it in a separate diagram. For future reference, the 10A K fuse that powers the back up lights is powered by a black/red wire that is spliced and runs between the ignition switch and an ignition relay. The relay contains the colors black, black/red, white/green and white.