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Jayro

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73 mustang baby blue with clevo 351
Ok so I’m getting absolutely no where on this car 😭

Is there a way to short out a couple wires to try get it to crank. A gentleman mentioned short out main + on battery and S terminal on starter solenoid. I assume that’s correct?

Even doing that I’m getting zippo action but everything meters 12.7v off the battery.
 

Hemikiller

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71 Mach 1
71 XR-7 coupe
71 Country Squire
65 coupe
I recommend you get yourself a remote starter. One lead goes to Battery (+), other lead clips to the "S" terminal.

If you get nothing, not even a click, from the solenoid when you short the (+) to the S terminal, then double check that the solenoid is properly grounded. If you still get nothing, then the solenoid is likely bad.

1668779240342.png
 
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My all time favorite vehicle is our 1969 Shelby GT500
I have found several uses for a remote start button switch like the on HemiKiller shows a photo of. Most recently I used it to (try to) send battery voltage through an alternator's field circuit, with an inductive ammeter clamped around one of the two wires, to see how many amps were flowing through the field circuit (I suspected a open circuit). I was able to do that without the engine running. It should have shown a few amps had the circuit not been open. It turns out I was indeed getting 0 amps flowing, so the field circuit was open. There are a few things that could cause that; bad wiring, bad rotor, bad brushes come to mind right away. But it turned out it was a brush holder that allowed a spade terminal for the Field circuit to slip back in the brush holder as opposed to locking the spade terminal in a fixed position. Sometimes the alternator would charge, when the loose spade terminal managed to somehow tough the field circuit terminal in that socket. But usually it would not charge as the connection was mostly open. It was vexing to figure out, but using the remote start button to try to send battery current through the field circuit at least got me into the right area to examine more carefully. It was such an unusual situation that I actually pur together a YouTube video showing what I found, and described how it was fixed, FWIW. For anyone interested in that video it is at:



In the video I did not use the remote starter button switch to send battery voltage to the Field circuit. I used a much smaller gauge jumper wire. But when I first ran through the diagnosis I used the remote start button switch to help make certain I was only sending current to the Field Circuit when the button was pressed, for more control of when current was being sent. It made sense to have more control over that situation at the time, as at the time I was not sure what I was dealing with (Short to ground was a possibility, where had that been the case I would want to be able to interrupt the current I was sending via the bypass as quickly as possible)
 

dkgd91

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france
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ford mustang 1971 V8 351 C
I recommend you get yourself a remote starter. One lead goes to Battery (+), other lead clips to the "S" terminal.

If you get nothing, not even a click, from the solenoid when you short the (+) to the S terminal, then double check that the solenoid is properly grounded. If you still get nothing, then the solenoid is likely bad.

View attachment 69898
What do you call the "S" terminal ? That's interesting for my future use
 

Hemikiller

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71 XR-7 coupe
71 Country Squire
65 coupe
I have found several uses for a remote start button switch like the on HemiKiller shows a photo of. Most recently I used it to (try to) send battery voltage through an alternator's field circuit, with an inductive ammeter clamped around one of the two wires, to see how many amps were flowing through the field circuit

Good alternative use of the remote switch, I may have to modify my spare with an assortment of terminal connectors.

What do you call the "S" terminal ? That's interesting for my future use

Most manufacturers label the solenoid with S and I molded into the housing over the terminals. S is the terminal that activates the solenoid, closing the internal contacts. I is the ignition booster connection, that supplies battery voltage to the ignition coil during cranking.

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