This is a little bit of a guess from your description of the mod.
It is not uncommon for wires to break in the loom in the area below the fuse box and going towards the small fuse box in front of the battery.
Possibly what you are describing is someones workaroung.
One my car pins 3 and 20 on the ECM connector had no voltage, they should be permanent 12 volts.
It's an extremely long story which would take a small novel to cover everything, so I'm going to skip to the end.
I replaced the loom, didn't fix the problem, although my original loom had 1 completely broken wire and a good number charred.
I stripped back the insulation checking for continuity every 6" or so, got all the way back to the base of the main fuse box.
From the bottom of the box there was no continuity to any fuses or relays, solution was to make a bridge bottom to top through one of the large 40 amp fuses.
Problem solved.
I have much more information and photos etc if you think you may have a similar problem.
It is not uncommon for wires to break in the loom in the area below the fuse box and going towards the small fuse box in front of the battery.
Possibly what you are describing is someones workaroung.
One my car pins 3 and 20 on the ECM connector had no voltage, they should be permanent 12 volts.
It's an extremely long story which would take a small novel to cover everything, so I'm going to skip to the end.
I replaced the loom, didn't fix the problem, although my original loom had 1 completely broken wire and a good number charred.
I stripped back the insulation checking for continuity every 6" or so, got all the way back to the base of the main fuse box.
From the bottom of the box there was no continuity to any fuses or relays, solution was to make a bridge bottom to top through one of the large 40 amp fuses.
Problem solved.
I have much more information and photos etc if you think you may have a similar problem.