S13 10 amp engine cont wire missing. Need Help

[erik240sx]

Was wondering if anyone can help me out with a problem I have concerning a problem I have with my wiring. A little background on the car. Its a 91 s13 coupe that used to have a rb25 but was removed and I bought the car as a shell and put a ka24de 5 speed and everything else on the car is stock. The problem I am having is with the fuse box closets to the battery. For the fuse labeled 10 amp engine cont I am missing the wire that is supposed to be connected to the fuse. Does this wire go to the ecu or where does it lead to? I looked at the wiring diagram but I have a hard time reading those. If anyone can point me in the right direction I would greatly appreciate it.