Starter cable melting

MOTMOT

MEMBER
2005 FORD CROWN VICTORIA
4.6L
V8
2WD
AUTOMATIC
160,000 MILES

I drove my car to a local auto parts store, after about 1/2 hour later I went to start it and the battery was dead, so I bought a new battery and when I turned the key all the way The positive cable going to the starter went up in smoke,
my car has 3 positive cables going to the positive post, 1 to the starter, 1 goin to the alternator, and 1 goin to the fuse box under the hood, Since all 3 are hooked together at the pos. Post, How can just the starter cable fry and not the other two? I know alot but this one's got me stumped, please only respond if you know for sure what it is. Thanks

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3 Replies

KASEKENNY

MECHANIC
18,907 POSTS

This is because you had high resistance in this one cable. If you want to confirm this then you can do what is called a voltage drop test on the wiring.

https://www.2carpros.com/articles/how-to-check-wiring

Basically you put your meter leads on the ends of this wire and then crank the engine. More then likely you will see a couple volts. You should not see much at all but you are seeing is the amount of voltage that the wire is using. In more cases you should see a couple tenths of a volt on this test on a cable like this as we want all the voltage getting to the starter for it to use.

What I would do is change the starter and then do this test again just to make sure the wire is okay.

The only other thing that would cause this is a starter issue but if this is operating properly then I doubt it is the issue.

I attached the process for this just in case you need it.

Let us know what you find.

Thanks

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