Reworking 2010 Express Harness
 

Hi. I am wondering if anyone can point me to some good resoruces on reworking the harness to use it in my nova. I know I can buy an aftermarket harness, but I have a decent harness now so I figured I could at least try to get it to work and save the $1500.

So specifically I am wondering what the ecu and bcm will complain about if it is not connected. Things like ABS, airbags, seatbelts, are these needed or can I just depin them?

Also I am assuming I can remove the factory AC wires and replace it with vintage air provided it is the right size fuses.

One other thing is the controls on the steering column. I was guessing that I can connect my Nova's controls in place of the Van's for the indicators, wipers, and hazards. Any ideas about the cruise? I am thinking this is just some buttons and I can cut the wires and make one out of toggle switches.

I have the wiring diagram, but what I cannot find is what the computers looks for before throwing a code.

Lt1swap.com has all the guides and pictures to do it and the pin outs and lists of what you need to keep and don't need. Just look under the harness info sections. There is hours and hours of reading in there. He covers all the bases.

The turn signals and cab electronics are largely separate from the VCM. You're going to use your nova stuff for all that. The harness you basically trim down to 3 wires, a 12v constant, a ground and a 12v keyed. When you do the swap you have to get the VCM re-flashed to deactivate a whole bunch of stuff which will include the VATs system and any thing else that would prevent the computer from letting the engine run due to a laundry list of things not having a sensor hooked to them anymore.

I believe you want certain A/C wires left in because the computer will change timing advances and stuff to compensate for A/C. But the guides on lt1swap are super thorough about it.

Lt1swap.com has all the guides and pictures to do it and the pin outs and lists of what you need to keep and don't need. Just look under the harness info sections. There is hours and hours of reading in there. He covers all the bases.

The turn signals and cab electronics are largely separate from the VCM. You're going to use your nova stuff for all that. The harness you basically trim down to 3 wires, a 12v constant, a ground and a 12v keyed. When you do the swap you have to get the VCM re-flashed to deactivate a whole bunch of stuff which will include the VATs system and any thing else that would prevent the computer from letting the engine run due to a laundry list of things not having a sensor hooked to them anymore.

I believe you want certain A/C wires left in because the computer will change timing advances and stuff to compensate for A/C. But the guides on lt1swap are super thorough about it.


I have heard of LT1swap before but never really paid it much mind because LTs are different than LSs, but holy crap that is a lot of good info. Thanks
This might be dumb, but I took all the wiring out of the nova. My idea was to use the Van's stuff in its place. Is that stupid? Should I put the old nova harness back? It was just crusty and gross looking.
I am assuming the AC from vintange air goes to those stock ac wires. I will look again at the site to see if it is mentioned, but dude is not too far from me. It would be on my way to LS fest in September.

Post #3 is all white print on light blue background and can't be seen.

that was weird...

Yeah! lol All good now!

Ya dont throw the nova stuff away. You have an engine harness and a chassis harness and in some vehicles a dash harness. The nova engine harness is going to be mostly junked for you. You want all the nova chassis harness left in place. All your lights, turn signals, etc...

Now, you could put all that new chassis harness and dash harness in the nova. The hours it would take to shorten and rework, trace all the wires out....nightmare in my opinion. No one really does that on a swap. You just remove 99% of the old engines harness and keep 2 or 3 wires from it. Usually something 12v keyed that ran to the novas coil and the starter wires and alternator wires, engine grounds, etc...That site will tell you how to trim it down to 3 wires to make the LS engine fire up and work. There are more than that you should keep, but the minimum to make it work is actually 3. You'll probably want a speed sensor signal, electric fan control wires and some other stuff as well as the A/C triggers.

But the VCM, at least gen 3 stuff, doesn't care about turn signals or door ajar warnings, etc...it just cares about the engine and the transmission. A lot of the chassis stuff for turn signals and crap like that is actually handled by the factory radio...

I was just thinking about using the van stuff since I had it, and the Nova stuff was crusty and gross. Thought I could save the $500 for a new chassis harness and just rework the Vans since it has everything I want.

All of the connectors will be different. The amount of wires will be different, the lenght, everything. Don't over think it.

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The $500 you think you will save on a new harness would be spent trying to make a van harness work in a car.

go to painless, pay the price for a replacement Nova chassis harness with all the correct connectors and everything cut to he perfect length, loomed, etc...

While wiring is a skill everyone needs to do stuff like this....it is also how most cars that burn down catch on fire to start with. When it comes to the chassis where it gets wet and deals with the elements and lots of rubbing on the body and chassis. I always try to just get painless stuff unless the bill is to ridiculous. If you don't go painless, you have to solder, shrink wrap, glue seal and all that stuff. By the time i buy shrink wrap, solder, flux, tape, looming, replacement wire spool of different colors and gauges....I've spent the amount the pre-made one costs. Unless I want something custom added it is not worth it.

I'm trying to not over think it. I'm assuming that I can just connect the components from my car into the fuse from the van. What problems are you seeing? Like if I run a wire from my headlights to the fuse panel to the Vans switch, what is the issue?

So how do you use the pedal, cruise, and the feature where when you remove the key and certain components stay on for 10 min or until the doors are opened? From what I gathered from painless it would be $2500 to get all the wiring I need because their harness does not work with the stock DBW pedal.

Care to explain?

After telling us how rotten the old car harness is, you would spend a small fortune on new connectors buying them piecemeal, and that's only if you can find them separately.

What do you mean connectors? Like if I buy some led headlights, can I not run wire from the headlight harness back into where the van headlights were suppose to connect? Like I am just talking about the BCM and a component, like lets pretend I do use a painless harness, can I still use the BCM by just splicing in the wires?

I think I understand what everyone is saying now. It is a bad idea to try to diy a wiring harness because of length, wire color, and connection integrity.

Wires attach to connectors. Connectors clip or push onto components. Wires do not directly attach to lights, etc. The van wiring will need Nova connectors. Connectors are not the same from car to car or car to van.

I was under the assumption that I could splice a wire to the pigtails of the connectors.

IF the connectors are still good. They get brittle after 40+ years.