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Discussion Starter · #1 ·
one day i tried to turn on the car the battery was dead, so i jumped it and drove the car about 50 miles. next morning the battery was dead again. so i went to pepboys and bought an optima red top that ran me about $150. same problem tried turning the car, 2 days later and it was dead again. i thought it had to do with the yellow top sitting in the trunk. i unplugged the yellow top let it sit overnight same problem in the morning battery was dead again.anybody having same problem,any ideas?
 

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Yep...if your alternator is bad, youll go through batteries like crazy. Youll ruin the battery.
Your alternator isnt re-charging the battery like its supposed to be doing....and everything is running off your battery.
 

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If your alternator isn't supplying enough power to supply the load including charging the battery, the battery icon light on your instrument panel should stay lit. When you turn the ignition key to on (do not start), does the battery icon light come on and then go out when you actually start the car. If the light goes out, I doubt its your alternator. Are you sure that some equipment isn't on and draining the battery?
 

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bring it somewhere and have a test put on the charging system(alternator) and battery.
if thats good then you have a drain that you need to find.
more about that after the test.
 

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Discussion Starter · #8 ·
i unpluged da system but it still draining da battery. da battery icon goes out after starting da car
 

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Like scottpassat2.8 says take it somewhere and have the battery / alternator checked. Any electrical work/changes to the car? If you have a voltmeter, start car and measure voltage while running it should be around 13.5 Volts or more. If not above 13 Volts, alternator is probably bad. If above 13 Volts, run for 15/20 minutes or so with all load turned off to charge battery. Turn car off. After 5 minutes or so, measure battery voltage. It should be around 12.7 Volts for a fully charged battery. Every hour or so measure battery voltage to see how rapidly it is discharging.
 

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you have a parasitic drain somewhere. start by doing a current draw measurement to see how MUCH of a drain you have and from there you can test individual circuits at the fuse panel. i'm thinking trunk light though.
 

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14 Volts indicates a good alternator. Battery voltage of 12 volts is way too low with the car off. That's only about a 25% charge. Make sure all your battery connections are tight and the cables are not corroded. Did Pepboys install the battery and check the charging system? I'd go back to Pepboys and have them check the Red Top battery. Tell them its not holding a charge.
 

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from an old post...

Current drain on the battery can be checked with an ammeter. Make sure the ignition is off, then disconnect one of the battery cables. Connect one ammeter lead to the battery and the other to the cable. The normal current drain on most vehicles should be about 25 milliamps or less. If the key-off drain exceeds 100 milliamps, there's an electrical problem that requires further diagnosis.

Finding the hidden current drain can be time consuming. The easiest way to isolate the problem is to pull one fuse at a time from the fuse panel until the ammeter reading drops. This will tell you which circuit is draining the battery. Then you have to check the wiring and each of the components in that circuit to pinpoint the problem.
 

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14 Volts indicates a good alternator. Battery voltage of 12 volts is way too low with the car off. That's only about a 25% charge. Make sure all your battery connections are tight and the cables are not corroded. Did Pepboys install the battery and check the charging system? I'd go back to Pepboys and have them check the Red Top battery. Tell them its not holding a charge.
What? I thought all car batteries were 12 volts. Now, if he had 12 AMPS, then that would be a problem.
 

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I have a question about hooking up an ammeter permanently to the car as a gauge. So I know how to hook up the ammeter, but how big do the cables need to be? I have the gauge and it says 10 gauge wire, but thats a lot smaller than the battery cables are. If I run 10 gauge wire will I run into a problem? Will the current from the battery fry the wire? Thanks guys.
 
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