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Is there a gremlin living under my hood?

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Old Nov 9, 2010 | 04:46 PM
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WalkDMC's Avatar
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Is there a gremlin living under my hood?

Electrical gremlins are fun. Now this could just be my alternator just decided to stop working on me, but something's fishy.

Symptom 1: my S4 will not charge itself, hell I can't even push start it. It will run if I get a jump though. Alternator belt is fine, and no squeaking while the motor is running.

Symptom 2: I pulled off the negative terminal from the battery and connected a voltmeter in between the post and terminal. With the positive lead from the alternator disconnected, I still get voltage which leads me to believe that there is a short somewhere else in the system. I pulled each fuse individually to see where the short might be and that did nothing.


Any thoughts/rants would be welcome.
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Old Nov 9, 2010 | 05:08 PM
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From: tulsa,ok.
When you disconnected the negative battery terminal and used the voltmeter to read voltage you're supposed to get a voltage reading that is close to the battery voltage as the voltmeter is creating a bridge between the post and the clamp.

What you want to do instead is set the multimeter to read as many amps as possible and then place the red meter lead to the negative post and the black meter lead to the clamp and take a reading which represents the amperage drain. No key is necessary and you want all lights off such as the light that turns on with the door open. When you take this reading and it is above what it should be then begin to remove the fuses one at a time and check to see if that lowerrs the amp drain if one is present. Do this test about an hour after you have used the car because there are some circuits in the car which can take upwards of 30 minutes or so to shut/power down and stop using voltage.

EDIT: You'll want to test for the drain with the alternator fully hooked up at first and then disconnected.
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Old Nov 9, 2010 | 05:22 PM
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You can also test the alternator by running the car and putting a volt meter on the battery with the headlights on. If the voltage consistently and continuously drops it is likely a bad alternator.

Also..

Have you fed your car after midnight or gotten it wet, I hear you should avoid those things.
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