What have I gotten myself into.....Help!!

[Zee]

So I've recently obtained a '90 4 banger, was originally an automatic truck and the 2nd previous owner from me has converted it to 5 speed. The person I bought it from has done a number on it. When I got it about a week ago, the dash was torn out and wires have hacked. I've got the wiring sorted out, I hope, but have 2 wires out of the fuse block that go to horn and brake lights that I have to figure out how to reinstall due to burnt wire/hack jobs.

.....ANYWAYS.....I also have 2 other trucks a '97, that's currently having the motor completely rebuilt, and a '94 4 cyl 5 speed that the frame is about to fall in half due to rust. My question is, can the entire harness out of the 94 be pulled and installed on the '90 and be fully operational like it was meant that way from the factory? Time is also a factor and I never seem to have enough of it, so what's the best option? Should you need more details feel free to fire away.

[ahardb0dy]

The brake light wire goes from the fuse block, to the brake light switch above the pedal and out to the brake lights.

[Foul_Mouth]

The harness should be the same for both trucks.

[Zee]

Originally Posted by Foul_Mouth

The harness should be the same for both trucks.

I don't think that's true, I've got a digital speedo in the '94 while the '90 is cable driven. I also have connections from when the auto trans was in. And the green wire I mentioned goes from "horn" fuse, but runs to a auto trans connection harness in the engine bay. I'll get some pictures up to help explain my struggle.

[ahardb0dy]

The gauge clusters are different as will be the harness for the cluster. If you wanted to swap the 94 harness into the older 90, you would need to transfer the parts from the 94 over also

[Zee]

Originally Posted by ahardb0dy

The gauge clusters are different as will be the harness for the cluster. If you wanted to swap the 94 harness into the older 90, you would need to transfer the parts from the 94 over also

I plan to swap everything in the dashboard and the dashboard itself. From what I've gathered when I do so, it's easier to do the entire chassis harness, engine harness, etc etc.

I should mention that I'm trying to reverse engineer what previous people have done to get the truck running properly, I started it the other day and I can start it now, I just need it to pass state inspection so I can put it on the road and park the '94 in order to pull harness/dash.

After doing some investigation today, found that the green wire I mentioned earlier is going from the fuse block in the "radio" fuse, to the radio, then to a relay in the engine bay next to the wiper motor. My assumption and from what I've found, the wire is burnt due to a 20 amp fuse being put where a 10 amp is originally called for. But now I have to tear harness apart to ensure no other wires got .

[Kawabuggy]

The wire did not burn simply because they put a larger fuse in.. The wire burned because the amperage draw was larger than the gauge of wire could support, or there is a short somewhere in the line. I hope you are able to find the real problem and get it solved.

[91nissan94]

If it was me I would just swap the harness and intake manifold out of the 94. You can actually just change from the throttle body up. You will need to change the speed sensor in the trans. Everything else is pretty much the same. I went from 91 to 94.

[Foul_Mouth]

You are right, I was incorrect. The 90 does use a cable driven speedo. The bulk of the harness will be pretty close though.