Wiring problems Mustang -73

[nursieee]

Trying to understand if this is right.

First is the battery, then are there the starter solenoid. On the first pin of the solenid there  is + from battery going in

and a Yellow or yellow black cable(hard to see the color) which goes to the alternator regulator (marked with y)

and there is also i cable connected to a short stop 12v 40A (dont see this one in the wiring diagram). (marked from +)

From the second pin of the short stop there is red-orange cable (marked r-o) that goes all the way to the alternator gauge? Which never did work. Should it be wired like that?

And there is also black thick cable from the second pin of short stop (marked 1) and the red thick one (marked 2, if you follow the arrow direction you end up in the alternator) if you follow it the other way you find that those to thick cables, red and black are soldered together to two 10 inch stubs, one thin yellow and one thick red (see picture 2) and they are spliced to one thin yellow and one thick yellow and those 2 goes trough the firewall. What is this or how should it be?

(For now i also have to bypass the shortstop with a cable otherwise the car dont start so it seems broken.)

Anyone who can explain this to me or tell me how it should be?



the red cable seems to come from the alternator (its the one marked with 2 on pic 1)and the black from pin 2 on the short stop(marked 1)

So the easy question is, what do i do?

 

[Don C]

It looks like somebody did a few modifications. Originally the power feed from the alternator to the battery and the power feed from the battery to the various circuits were protected by a fusible link. It looks like someone replaced the fusible link with a circuit breaker (short stop). And, you are likely correct, the circuit breaker has failed.

The attached wiring diagram should help you. In this diagram circuit number 36C would be the fusible link.

 

[midlife]

So the easy question is, what do i do?

Junk all of your wiring and go with reproduction or refurbished wires. Someone has seriously altered what you have, and no one on the forum will likely be able to diagnose what each wire does, as they are not factory correct.

 

[Don C]

The ammeter works off a shunt circuit, meaning that the full current load does not pass through the ammeter, instead only a small portion of the current is passed by the shunt through the ammeter. The wiring damage (likely burned up) that caused someone to try to repair the wiring likely also damaged the shunt circuit or was bypassed during the "repair". The ammeter may also have been damaged.

Unless you are very experienced with automotive wiring and have a good understanding of electrical flow theory it would be very difficult to build your own shunt circuit.

Midlife repairs and rebuilds wiring harnesses for our cars and may be your best bet to get it all functioning correctly.

If you are able to get everything except the ammeter working you can have Rocketman convert your ammeter to a voltmeter.

 

[mjseakan]

Not being afraid to show my ignorance I'm going to ask this question:

 Is shortstop a common name for a circuit breaker? 

I've never heard one called that before but it makes sense, kind of.

Mike

 

[Don C]

He's from Sweden, so they may be called something else there, or it may just be a translation anomaly.

 

[nursieee]

He's from Sweden, so they may be called something else there, or it may just be a translation anomaly.

Its both a languageproblem, i dont know the swedish word for it and it is my first contact with electrical wiring in cars so i googled it, found a picture of it and simply named it shortstop. So from now on i think i´ll call it circuit breaker.

 

[Don C]

Short stop accurately describes it, just easy to confuse it with a player position in the game of baseball

 

[mjseakan]

You could say it describes its function perfectly:

 short stop -  stop a short ... maybe?