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Help! Solenoid and Starter Wiring

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Old 03-16-2008, 12:28 PM
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REAVER117
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Default Help! Solenoid and Starter Wiring

I'm troubleshooting why my Mustang won't start, testing it one lead at a time. Right now when I turn the key the solenoid (which I replaced because the car wouldn't start) clicks but the engine doesn't turn over at all, which leads me to believe that the problem is either the wiring or the starter. While testing the wires to the solenoid I found that both the cable that runs from the alternator to the battery terminal of the solenoid and the cable that runs from the starter to the solenoid were grounded, is this normal? It would really help me if someone with a multimeter could go out and check what terminals of the solenoid connect to ground (with the continuity test mode), cause right now the only one that doesn't have a connection to ground is the coil terminal.
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Old 03-16-2008, 12:40 PM
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Default RE: Help! Solenoid and Starter Wiring

The solenoid is grounded by bolting it to fender apron. Then one heavy cable from one side of solenoid down to starter. The other side gets the battery lead and the alt. wire plus any other 12volt outgoing wires. Then there be the small trigger wire the small post in front of solenoid.
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Old 03-16-2008, 12:43 PM
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Default RE: Help! Solenoid and Starter Wiring

Yeah, I know the actual wiring connections, but what I need to know is if any of the posts is connected to ground when the car is in park, because right now I'm reading 3 of the 4 posts as being grounded, which is especially bad considering one of the posts connects directly to the +ve lead of the battery.
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Old 03-16-2008, 12:55 PM
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Starfury
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Default RE: Help! Solenoid and Starter Wiring

The onlything that should be hooked up to the battery post on the fender solenoid is the cable to the positive battery terminal. Grounding anything connected to that terminal (remember, nothing should be connected to it in the first place) would cause a short and either melt the wire instantly or possibly cause the battery to explode.

What wires do you have running where? And how are you testing them?

What you need to do is grab a multimeterandconnect the blacklead to ground andthe red lead to the power lug on the starter. Set in the voltmeter mode, it should read 0V. Jump the large battery post of the solenoid to the small terminal directly adjascent to it and look at the meter. Come back with your readings.
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Old 03-16-2008, 01:05 PM
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Default RE: Help! Solenoid and Starter Wiring

Ok, well right now the battery terminal of the solenoid has the cable to the battery, the cable to the alternator (which splits off and connects to the voltage regulator) and some wire that goes through the dashboard. I didn't setup the wiring that's how it was when I bought the car, I can't test the voltage right now because the battery is completely dead, but the car doesn't even start when I jump it. I'm testing using the continuity test on themulimeter, and when I test the individual wires the one that goes to the alternator and splits to the voltage reg is grounded, same with the cable that goes to the starter and the ignition switch.
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Old 03-16-2008, 01:35 PM
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67t5ponycoupe
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Default RE: Help! Solenoid and Starter Wiring

Cars use a grounded system.In other words you run a positive lead to the load and then ground the other side, that makes it work. If you are messuring ground that means you are just messuring through the componant to ground. That is right. Get a good battery in the system and try it again. I think you are trouble shooting for no reason. If your battery is really dead it will cause all kinds of problems.
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Old 03-16-2008, 01:38 PM
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Default RE: Help! Solenoid and Starter Wiring

BTW everything that gets power on the entire car get power from the positive side of the soleniod. There should be a bunch of stuff hooked up there.
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Old 03-16-2008, 01:44 PM
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REAVER117
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Default RE: Help! Solenoid and Starter Wiring

Yeah, I understand how the system works, but the problem is something in the wiring/electrical system killed the battery. Using continuity testing should not detect a connection to ground, since a direct connection from +ve to ground woulb mean a short to the battery, if there is a load between the connection the continuity test won't indicate a connection. All I really need is to know is if any of the connections, especially the solenoid, is grounded on the solenoid terminal. My thinking is that the solenoid is sending current to the starter, but since there is a short somewhere between the two the current is getting grounded back to the battery. Even if I have a bad starter shouldn't the starter still try to crank?
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Old 03-16-2008, 01:48 PM
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Default RE: Help! Solenoid and Starter Wiring

let's start from scratch. what's a continuity test? I guess it's a check for resistance, measuring ohm
from that I don't see why any of the cables tehre should go to ground and as starfury says it would shorten out.

with a resistance test you can't really check much, only lets say:
battery+ to battery side of terminal should be 0 ohm
starter+ to starter relais on starter side should be o ohm

i and s port of relais should be endless resistance to + and - when key is in off position.

I'd say we'll have to go a different route as you have no battery the only thing we can do for now is to check your wiring.
What year is it and we'll pull out the diagram

kalli


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Old 03-16-2008, 01:54 PM
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Default RE: Help! Solenoid and Starter Wiring

Dude you are over complicating the heck out of this. The best couse of action is to get a good battery and start from there. If you have a dead short, like you are saying, you would have a fire in the harness.
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