Alternator fuse keeps blowing

Tiny
DOUGIEP15
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Used a test light on my starter solenoid not sure if that plays a factor.
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Friday, November 6th, 2020 AT 5:55 PM
Tiny
KASEKENNY
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Just to jump in and answer that question. It appears that is the control wire on the starter. You should only have 12 volts on that when you are cranking the engine. So if you were not cranking the engine when you tested with with your test light then it would not light up.
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Friday, November 6th, 2020 AT 6:11 PM
Tiny
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Thanks for the response, in regards to the picture I posted, I was not cranking the engine.
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Friday, November 6th, 2020 AT 6:22 PM
Tiny
JACOBANDNICKOLAS
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Hi,

That wire only gets 12v when the key is in the start position. So what you found is normal. Have you checked the connection at the alternator? If you have and it's good, remove the alternator and have it bench tested at a parts store. Most will do it for free.

Again, since the fuse only blows when the alternator is connected, then it is most likely the alternator or the connector.

Let me know.
Joe
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Friday, November 6th, 2020 AT 6:26 PM
Tiny
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Not sure if this would cause the alternator fuse to keep blowing. I followed the cord from what you see in the picture all the way up to the instrument cluster.
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Saturday, November 7th, 2020 AT 3:34 PM
Tiny
JACOBANDNICKOLAS
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What wire is that in pic 1? Where does it go? That certainly needs attention.

Let me know.
Joe
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Saturday, November 7th, 2020 AT 3:39 PM
Tiny
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Hey Joe, that burnt wire leads up into the instrument cluster.
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Saturday, November 7th, 2020 AT 3:42 PM
Tiny
JACOBANDNICKOLAS
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If you shield it, does the fuse still blow?
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Saturday, November 7th, 2020 AT 3:45 PM
Tiny
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Going to try right now.
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Saturday, November 7th, 2020 AT 4:06 PM
Tiny
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Still blows when I shield it.
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Saturday, November 7th, 2020 AT 4:26 PM
Tiny
JACOBANDNICKOLAS
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I was hoping that was the issue. However, it needs repaired regardless.

Have you checked at the alternator (plug) or had the alternator itself bench tested?
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Saturday, November 7th, 2020 AT 4:45 PM
Tiny
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Took the wires that go from the starter solenoid to the alternator apart and inspected. Everything seems fine but haven’t gotten it bench tested yet.
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Saturday, November 7th, 2020 AT 8:18 PM
Tiny
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Hi,

I'm more interested in the yellow wire between the fuse and the alternator. Have you inspected it along with the connector?

Let me know.
Joe
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Sunday, November 8th, 2020 AT 4:12 PM
Tiny
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This is the diagram for my 2003 Ford F-150, I’m bringing my alternator to do bench test tomorrow after work.
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Sunday, November 8th, 2020 AT 6:04 PM
Tiny
JACOBANDNICKOLAS
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Hi,

Sounds like a plan. Let me know what you find. Also, when looking at your schematic, it's a bit blurry. However, it looks the same. Is there something different you are seeing?

Joe
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Sunday, November 8th, 2020 AT 7:26 PM
Tiny
DOUGIEP15
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Hey, just wanted to thank you for your time. I got my alternator bench tested and it was fried. Got a new one put the fuse in good to go.
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Thursday, November 12th, 2020 AT 3:13 PM
Tiny
JACOBANDNICKOLAS
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Hi,

You are very welcome. I had a feeling it was either the connector at the alternator or the alternator itself. Regardless, good job. I'm glad you got it working again.

Please feel free to come back anytime in the future. You are always welcome.

Take good care of yourself,

Joe
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Thursday, November 12th, 2020 AT 6:44 PM

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