How to tell which factory wiring harness I have?

[DirtDonk]

I think we have mentioned over the years, and Viperwolf1 and probably you have given some good information on, the fact that some different colors are interchangeable and will work, while some different colored modules will physically connect, but never work because the wires are oriented differently.
While still others will not physically connect.

 

[DirtDonk]

Here is my buddy’s ignition module plugged into my harness. It’s a Wells which I’m not sure if this was OEM or not.

Thanks for the picture.
Wells may very well have been a factory supplier, but I believe if you buy one with the Wells name on it, it is strictly an aftermarket replacement.
I could be wrong, but I think that’s how it worked.

From here at least it looks like the wire colors do not line up properly. That can be changed in the two wire plug, but I can’t see the other plug clearly.
Is there even a green trigger wire coming out of that one? Can you twist the connections for a better view and post the picture?
Thanks

 

[Gas Pig]

Yes after you guys pointed out the different pinout out from my 76 harness to my buddy’s 75 module… I think it would make most sense just to buy a new module. At least it will be new and one less thing to worry about!

 

[DirtDonk]

At least it will be new and one less thing to worry about!

Haha! Silly wabbit…
Never was that statement further from reality.
New parts are actually the most common problem that is hard to track down because we expect the new part to work. And unfortunately high percentage of new parts either fail early or do not work right out of the box.
Sad but true.

 

[Gas Pig]

Haha! Silly wabbit…
Never was that statement further from reality.
New parts are actually the most common problem that is hard to track down because we expect the new part to work. And unfortunately high percentage of new parts either fail early or do not work right out of the box.
Sad but true.

Yes, that couldn’t be a truer statement! I guess I was trying to be an optimistic. On a couple of our builds, we ran into several of those problems with various different parts that were from different stores, different manufacturers and from different countries from which they were made in. So as much as I would like to blame the cheap Chinese parts they weren’t all made from China. Either way it’s very frustrating when you expect something to work as it should and it doesn’t… then the troubleshooting skills have to kick in!

 

[DirtDonk]

Yes, even US made parts have taken a huge step backward (like 100 years backward!) in the last 15 or 20 years. My guess it's just them trying to stay relevant by being cheap and competing directly with overseas parts. Cheap means bad even when made here.
They probably have to buy the materials and parts from overseas in the first place, just to make stuff here!

And it shows!
I know that's just a generalization. Probably lots of good superior stuff still made here. Just that more and more of it isn't...

Paul

 

[Gas Pig]

Hey I seriously don’t mean to be a clueless idiot here but man I’m stumped.

Im using a good 76 dash harness but I had to track down then alternator harness and the motor/ignition harness. I thought that wouldn’t have been such a problem but I was mistaken.

So I got a good alternator harness that is solid only the ground wire I need a new ring lug… no big deal. But this motor/ignition harness is a different story. I finally found one and all I needed was to clean it up and re-tape it. But as I was ringing out the wires I noticed the two connectors that plug into the dash harness, they are completely wrong. The square male has the three correct wires but my dash harness it three pin flat plug end. That’s something I can change easily enough. The larger problem is the four pin round connector. On my 76 dash harness it’s four pin female unfortunately my motor/ignition harness is also a 4 pin female. What the heck! Sp obviously I still have a miss matched harnesses here.

I’m thinking of taking and old ignition module and cutting off the 4 pin male plug end connector then splice it into my motor harness.

First of all is anyone know what year in this motor/ignition harness ‘77?

Any thoughts on this?

 

[Ovalis]

Hey I seriously don’t mean to be a clueless idiot here but man I’m stumped.

Im using a good 76 dash harness but I had to track down then alternator harness and the motor/ignition harness. I thought that wouldn’t have been such a problem but I was mistaken.

So I got a good alternator harness that is solid only the ground wire I need a new ring lug… no big deal. But this motor/ignition harness is a different story. I finally found one and all I needed was to clean it up and re-tape it. But as I was ringing out the wires I noticed the two connectors that plug into the dash harness, they are completely wrong. The square male has the three correct wires but my dash harness it three pin flat plug end. That’s something I can change easily enough. The larger problem is the four pin round connector. On my 76 dash harness it’s four pin female unfortunately my motor/ignition harness is also a 4 pin female. What the heck! Sp obviously I still have a miss matched harnesses here.

I’m thinking of taking and old ignition module and cutting off the 4 pin male plug end connector then splice it into my motor harness.

First of all is anyone know what year in this motor/ignition harness ‘77?

Any thoughts on this?

I couldn't tell unless I traced the wires back at each terminal and see what's feeding it, but maybe these pictures might help. 3 different harnesses for 74, 75, & 76/77. One way to tell them apart is to look for the location of the tabs on the connectors. The location of the tabs on the 74 is different so you can't accidently connect the wrong module to it. The the tabs on the 75 connectors I believe is the same as the 76/77 connectors but the difference between those two harnesses is the 75 has 7 wires total at the connector & the 76/77 harness has 6 wires at the connector. Hopefully these pictures might help you out.