Anyone built your own wiring harness? I would prefer to make my own custom length harness. I am planning on throwing a dmax in a grand national.
Know how to build a wiring harness?
- Thread starter Stancedlb7
- Start date
Let me preface this by saying I truly hate wiring. I did however manage to build a stand alone harness for my street rod after not getting a response from companies that sell stand alone harnesses, or them wanting much more than my budget would allow.
With that being said, I paid for a year of alldatadiy.com subscription for the year of truck I was using the engine out of to get all the connector pin outs. Once you have pin outs and wiring diagrams, it's just a matter of removing the circuits you don't need, adding fuses for the power inputs, lengthening/shortening and generally tidying things up. If you don't have the body harness from the truck, you'll have to add in the throttle pedal wiring and wiring from the bale connectors to the ECM.
Bear in mind, I didn't add in any BCM/TCM circuits since I used a manual VB auto. I did look a little at what's involved and feel fairly confident in saying it wouldn't add any much, if any, more difficulty than doing the engine alone, just more of the same thing you did to the engine harness.
You can even buy the connectors and pins for the ecm/pedal or anything else you might need if you start with only the engine harness and don't have the engine to fuse panel harness that comes in the truck factory. I'll see if I can find the notes on which website and connectors if that might help.
It's time consuming as hell, at least it was for me. I think buying a harness already done from a company who specializes in it is probably worth it considering the time involved but you can do it yourself relatively easily if you put in the effort.
Price didn't hit me that hard as there is a solid amount of time involved. I probably would have had him build me one if he wasn't so hard to track down. Nothing against Ben as I've heard he's the man when it comes to this type thing but it's rare for me to want to chase someone around begging them to take my money.
I did mine, and integrated it into my factory 95 wiring harness when I did it. The big thing is sitting down with ALL of the connector diagrams, and deciding what needs to stay, and what can go. Then figure out which ones are powers and ground, keyed power, constant power, then look and see if anything can be combined. Theres ALOT of work that goes into it before you start the 1st thing with the actual harness.
So I plan on using my lb7 mated to a manual VB th400. The truck caught fire so the harness is completely gone. I have lots of time and would rather use $900 for something else. But are you saying I can just buy the connectors, pins, and spools of wire and make a harness? Because that would be fantastic! The car will be strictly drag use only.I do have access to motorlogic but do you have a copy of the diagram by any chance? But yes links or websites would be very useful. Thanks for your help btw
Buying all of the connectors separately, wire, etc you're gonna be into it a lot more than $900 Ill tell ya that... Some of the connectors are impossible to find too, unless you buy 10,000 of them. The ECM connectors alone are close to $100 last I checked.
Not to mention crimping all of those pins if you were to start from scratch. I have several thousand dollars in crimping tools to do everything correctly...otherwise you're going to get crappy connections, wires that pull out, pins that dont seat properly, etc. You arent going to correctly crimp ANY pins on a duramax harness with the piece of crap $15 butt-splice connectors you bought at AutoZone.
Buy a good/used complete harness and re-work it. You'll be WAYY ahead in terms of time and money. I have a couple good spare LB7 harnesses here if you're interested.
ben
I basically turned the wiring from my van into a stand alone harness even though it was a factory application. I just recently moved a couple of wires and converted it over to a pickup operating system. I also built a stand alone harness for an LB7/Allison combo that was installed into a '29 model A which I integrated into a wiring harness I had to build for the rest of the car with a complete fuse box I had to put together. It was kind of fun and turned out pretty nice, but it was very time consuming. Like Ben said, if you build a complete harness from scratch, you are going to spend a lot of money (especially if you use quality components). Good luck with whatever you end up doing.
Empire builds them. It's best to Facebook message them, ive found. Mine was $800 but only because the truck harness i sent them was missing some plugs. Should be cheaper if you send them undamaged engine and/or truck harness.
Did anyone run into security issues when building their own harness? I'm concerned it will not start without ecm tuning since normally the truck wants to communicated between all the different modules BCM TCM ECM etc. I'm swapping over my lbz and am concerned once i've gone through and eliminated unnecessary wires and labeled those I need it won't work and I'll have to pay an arm and a leg for one of the companies that does it to re do it. I would think you might need custom tuning, but maybe that would only be if you want to use the factor dash and obd2? Or would the obd2 still work without any remapping?
You have to either keep the bcm for the ecm to turn the fuel on, use a vats bypass module to bypass the bcm, or have vats turned off in the ecm tuning.
I signed up for alldatadiy for my 2008 chevy duramax 4wd and I can not find ANY schematics at ALL!!!!!!!
I found a bunch of fuse diagrams but not the ECM wiring details like I need
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Look on the right side of the AllData page listing all the categories. Its there under the Shortcuts tab, "Diagrams"
I go to "Vehicle » Powertrain Management » Computers and Control Systems » Engine Control Module » Diagrams » Electrical Diagrams"
and it tells me to go to " Vehicle » Powertrain Management » Diagrams » Electrical Diagrams" there are just a few "snipits" but nothing that is going to help me.
I was looking at one guys video and he had sheets that had the complete ECM and TCM connector pin outs with ALL the wire colors, circuit numbers and what that circuit was.
These little boxes that will not even zoom are not going to get me where I need to go, I guess I will keep looking.
Thanks for taking time to try and help!!
and it tells me to go to " Vehicle » Powertrain Management » Diagrams » Electrical Diagrams" there are just a few "snipits" but nothing that is going to help me.
I was looking at one guys video and he had sheets that had the complete ECM and TCM connector pin outs with ALL the wire colors, circuit numbers and what that circuit was.
These little boxes that will not even zoom are not going to get me where I need to go, I guess I will keep looking.
Thanks for taking time to try and help!!