1981 wiring question

[BDCCLARK]

Somewhere upstream in the ownership chain of my 81 there was someone who really thought they were a better electrical engineer than the manufacturer.

My harness is littered with male/female spade connectors from front to back. I've removed all sorts of unnecessary wiring so far. I had a stand alone horn button with a dual aftermarket horn setup. Nothing special, but it was there and working. Inline fuse off solenoid for juice to the stand alone switch and back to the horns. My factory horn button and relay work fine, so I wired it back to the steering wheel button.

My concern is where my horn power comes from. There is no horn fuse. No fuses kill the power to it either. My best guess is it runs off the main headlight power circuit and is safety controlled with the fusible link. Yes/no?

Where is this fusible link? My guess is right off the solenoid, but again, my jeep has a much smaller wire there with a spade connector.

Positive information or even a picture would be fantastic help.

Chris

 

[Dave The Sparky]

The horn relay is here on the schematic, i will need to trace it back and see where it is fused from

 

[Dave The Sparky]

You are correct it is off a fusible link i have highlighted it in yellow. and looking at the drawing it must be on or adjacent to the starter solenoid.
So it sounds like you already knew the answers and just wanted some confirmation.

 

[BDCCLARK]

That looks like a great schematic. Where is it from?

You are correct, I was pretty sure, but I like to see schematics and I don't have one yet. How do we know what size it is?

Thank you Dave, Chris

 

[BDCCLARK]

What does the circle with the triangle symbol mean?

 

[Dave The Sparky]

What does the circle with the triangle symbol mean?

I think it just relates to the stud on the solenoid, PM me your email and i will send you the diagram or if you search about they are on the internet.

 

[BDCCLARK]

pm sent.

I wonder how we figure out what size fusible link to use.

 

[BDCCLARK]

The fusible link to the alternator is still there. The other one going straight to the headlights and such is just a wire with a spade terminal connecting it. work by someone who should find a new hobby. I hope whoever did it was a hobbyist and not a professional.

Chris

 

[Dave The Sparky]

Oh dear that does sound like a fire waiting to happen, luckily you found it.

For sizing fusible links i have no idea how the automobile manufacturers do it but i would work out how much load is on the link and then add a good healthy chunk of amps on top as it should be a last resort thing and never intended to blow in normal conditions.

Does make you wonder why its not there now though? whether they didn't know what it was or had actually blown who knows!

 

[BDCCLARK]

I agree. It's anyone's guess on why it's gone. On the bright side, I'm bringing it back to proper everyday.

Thanks for the help Dave

Chris

 

[Chamba]

Your PO and mine obviously learnt their skills from the same sparky; mine was littered with t- connectors and crimps . After years of chasing electrical gremlins I put in a painless harness: heaven. Worth every cent.

 

[BDCCLARK]

Did you buy the custom or the replacement harness?

 

[Chamba]

The standard one with all the terminals.

 

[BDCCLARK]

That's the one in the that is about $900 right? Does it come with factory style connectors for all the gauges and and instrument lights?

 

[Chamba]

That's the one. I got it from Quadratec, though it's a bit cheaper elsewhere. Had all the factory connectors including the dash cluster lights. I was truly impressed with the fit and quality. It even comes with all the light globes, fuses, relays, etc. I used all LED lights though so didn't use the incandescent globes they included.

I'll post a pic of the box when i get home.