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BJ8 Wiring Diagram in "Ladder Logic"

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Informatio that enhances understanding is always welcomed here on the forum.
 
Hi All,

I appreciate that many of us have used the original electrical diagram for so long that it is both familiar and, for many, the diagram is imbedded within our memories. Yes, it has worked, but not because it was the best, because it was the only. Bill's depiction is an implementation of the latest standard format in electrical graphics and is a reflection of both logic and flow within the many component functional states of our electrical system. This allows viewing and understanding of a component's/circuit's operatonal potential and how it will react when encountering a fault.

After a little time spent with this electrical format, I would not be surprised if you come to prefer it. Just give it a little time and effort to gain familiarity. Either way, you would now have a choice and it is yours to make.

Ray(64BJ8P1)


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I redrew the wiring diagram for my BN4 in color, then did the modifications using the ladder logic format. For those of us used to ladder logic it works much better in understanding how the system works. Being somewhat used to AutoCAD, I used that. My electrical drawings now cover three 11 x 17 sheets. I may have to do the whole of the wiring diagram in ladder logic.
 
The schematic and ladder logic diagram are both informative but what would really complement them would be a set of photos showing how the wiring is actually done; e.g. the rat's nest on the scuttle, in the front (with light harnesses), the OD, along the chassis, etc. If you're starting with a bare chassis and a set of harnesses I imagine it would be a challenge.
 
Bob_Spidell said:
The schematic and ladder logic diagram are both informative but what would really complement them would be a set of photos showing how the wiring is actually done; e.g. the rat's nest on the scuttle, in the front (with light harnesses), the OD, along the chassis, etc. If you're starting with a bare chassis and a set of harnesses I imagine it would be a challenge.
Click to expand...

I think the only way to do that would be to have a dashboard out of the car and take pictures of it all wired up from behind. When I see my dash from beneath, all I can see is the usual rats nest, which I'm pretty sure being the original harness in a car stored in a barn for 30 years actually housed real rats. I guess I'm pretty accustomed to the standard diagram but often get lost trying to follow the path of a wire. At least the colors aren't all in Italian like my Fiat diagrams were.
 
Hi Bob,

Rick has a point. It would take quite a bit of photography to deal with crating even a baseline of images. Back in the 1980s when I redid my Healey, I had the harnesses re-wrapped and paid for harness diagrams identifying each connector. This allowed me to lay in the harness and get a rough idea of its original routing and tie-down location after locating each component and matching the connectors. However, as a result, I have a good reference to point-to-point wire routing to match up to the original wiring schematic.

Wiring additions since then are not reflected but I did create additional diagrams for these additions and changes. The problem is that I could rely on my memories to some extend to tie all these components together and although well documented for me, and somewhat well documented for others, a future owner will still have a learning curve.

As an example, when recently rebuilding my Flasher Relay Box using (2) 8-pin DPDT relays, I changed the way the dash indicators were connected:

Converted Grounds FRB.jpg
How would this be implemented in a Ladder Diagram? How would the states of the 2 relays within be reflected so as to provide a quick understanding of the units reaction through its states? To create a clear reflection through a detailed Ladder Diagram would take a clear understanding of the device within the contests of the circuit's multiple states but would allow for a quick and complete update of understanding when revisited at a later time.

Ray(64BJ8P1)
 
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Years ago, Adnan Merchant, who was on the autox Healeys list at the time, made a CAD drawing of the BJ8 electrical diagram (Phase 2, dual indicator light) from the workshop manual, color coding each circuit. It included a color key. This was fine, but still was hard to read for me with all of the circuits on the same page.
For my own purposes, I took his drawing and made multiple black & white copies of it on 11 x 17 sheets, then made my own color-coded separate drawing for each circuit. I used colored pencils to trace out the circuit for brake lights, fuel gauge, turn signals, etc. on a separate sheet (16 pages in all) and put them into a "Wiring" notebook. I have found it to be a quick way to troubleshoot a circuit when a problem appears. I keep the wiring notebook in the boot so it's handy on the road if needed.
 
Legal Bill said:
Bill, great job. I sent you a PM.

I'm surprised no one mentioned this resource. i bought one years ago. So much easier to follow than the line diagram in the manuals.

https://colorwiringdiagrams.com/t/austin-healey
Click to expand...

Bill - do these have the second color on the wires? - from their samples the lines only looked single-color.

PS - did you ever get the 3/8" generator pulley? :cool:
 
steveg said:
Bill - do these have the second color on the wires? - from their samples the lines only looked single-color.

PS - did you ever get the 3/8" generator pulley? :cool:
Click to expand...

Yes. The charts have easy to read one and two color wires showing the minor color as a stripe inside the major color.

And no, I still don't have that pulley. Ha. The pressed steel pulley is still going strong, but is incorrect.
 
Very nice work Bill!! Please send me a .pdf file....ian.j.crisp@gmail.com

'67 BJ8, '69 Volvo 1800S
Portland, OR
 
A long time ago, Adnan Merchant, who used to be a participant on the healeys@autox.team.net email list, re-drew the factory workshop wiring diagram in a CAD program for BJ8s and color-coded the various circuits. I used his basic diagram, printed out in black and white, and re-printed it out on a 11 x 17 sheet. Then, I made copies of the basic diagram for each circuit, then used colored pencils to trace over each circuit (one circuit per sheet). I put these into a notebook that I keep in the car. With each circuit highlighted on its own sheet, it is easy to troubleshoot electrical problems.
 
Here is a rev E1 for the late BJ8
 

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