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More on the current draw issue... alternator

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tweety

tweety

Jedi Trainee
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Following up on my previous post regarding the battery dieing while parked.

I tested for current draw by using an ammeter between the negative post on the battery and the battery terminal. Got a current draw of 4.5 amps, yikes. (meter set to 10A range)

Checked for any changes while fuses pulled etc.... No difference, pull the wire harness on the alternator and bingo, down to .1 amps of draw.

I took the back cover off of the alternator and discovered that the a little yellow jumper wire connected to the terminals was amiss (see the linked pic.)

https://picasaweb.google.com/audiokook/MGTop#5403021489093198386

It was on the wrong post (at least not the one it was on when I bought the car.) I put it back on the post where it was when I got the car and checked again, this time 2.5 amps of current. The car started but the battery light in the dash stayed fully lit.

I moved the jumper to the third post, the current draw was back down to less than .1 but the battery light does not come on at all.

I'm guessing I need a new alternator?
 
How would a jumper suddenly find its way to the wrong terminal? This seems strange to me.

In any case, randomly trying connections on an alternator is a little dangerous. Be careful!

It does sound to me like something in the alternator is fried--I can't imagine any normal circumstances under which it would draw current at all.
 
Entirely my fault on the jumper thing......

In my car, you have to pull the plastic cover off of the back of the alternator in order to get at the first plug. In doing this, I accidentally knocked the jumper off of it's post.

My dyslexic mind must have taken over and I put it on the wrong post.

The pic is correct because I took it right after I got the car.

BTW, I drove the car last night, no problem. It sat over night and started right up this am. I'm going to let it be this weeks and see if the battery dies while sitting, or while driving. (it will be a town car for awhile)
 
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