Alternator/Battery problems.
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with the car running, use a multimeter to measure the battery voltage. it should be around 13.8V-14.4V. now put the multimeter into AC Voltage mode. measure across the battery again. you should measure 0V. if you see voltage while measuring in AC mode, the diodes are bad.
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From: Queen City, NC
Unless you're already replaced it, you have a six year old car with a 5-yr battery in it. I'm going to go out on a limb and say its an old battery. You are taking a simple problem and making it way too complicated.
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From: socal
So I took it to auto zone and they said my alternator is fine. I'm still a little skeptical because my tach sometimes flicker during idle. It isn't that noticeable but enough for me to see it.
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From: Dade County
Originally Posted by toniotran,Aug 30 2010, 11:30 PM
I believe you can check by removing the negative terminal off the battery after you've started the car and if it the car shuts off then it's usually a sign of a bad alternator...plus you'll know if it's the alternator now if the car begins having start up issues again since your dad replaced the battery. hope that helps
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From: Socal
Originally Posted by Mister Jew,Sep 2 2010, 09:17 PM
You've got it backwards. Start car and remove the positive battery cable not the negative.
http://www.wikihow.com/Check-an-Alternator
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From: Bellaire, Texas
Actually, it does matter but perhaps not for the reason that you are thinking.
Removing either cable will disconnect the battery. If you remove the positive cable, you have this "hot" post sticking out; touching anything to it that is also connected to the car will give you a short - and a good size spark. If you remove the negative terminal, all of the "positive" connections to the battery are still insulated. Accidentally touching the negative terminal of the battery to something connected to the engine or chassis merely reconnects what you have disconnected.
Disconnecting the negative terminal reduces the likelihood of receiving a nasty surprise with a dropped wrench or other metal tool.
Removing either cable will disconnect the battery. If you remove the positive cable, you have this "hot" post sticking out; touching anything to it that is also connected to the car will give you a short - and a good size spark. If you remove the negative terminal, all of the "positive" connections to the battery are still insulated. Accidentally touching the negative terminal of the battery to something connected to the engine or chassis merely reconnects what you have disconnected.
Disconnecting the negative terminal reduces the likelihood of receiving a nasty surprise with a dropped wrench or other metal tool.
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From: LaVista, NE
Originally Posted by idea-catalyst,Sep 3 2010, 07:56 AM
Actually, it does matter but perhaps not for the reason that you are thinking.
Removing either cable will disconnect the battery. If you remove the positive cable, you have this "hot" post sticking out; touching anything to it that is also connected to the car will give you a short - and a good size spark. If you remove the negative terminal, all of the "positive" connections to the battery are still insulated. Accidentally touching the negative terminal of the battery to something connected to the engine or chassis merely reconnects what you have disconnected.
Disconnecting the negative terminal reduces the likelihood of receiving a nasty surprise with a dropped wrench or other metal tool.
Removing either cable will disconnect the battery. If you remove the positive cable, you have this "hot" post sticking out; touching anything to it that is also connected to the car will give you a short - and a good size spark. If you remove the negative terminal, all of the "positive" connections to the battery are still insulated. Accidentally touching the negative terminal of the battery to something connected to the engine or chassis merely reconnects what you have disconnected.
Disconnecting the negative terminal reduces the likelihood of receiving a nasty surprise with a dropped wrench or other metal tool.
thats why you always disconnect negative first and connect last.
