04-27-2018, 12:27 PM | #1 |
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Bad Battery or Alternator?
I get the battery discharge warning every now and again right when starting the car or turning the car off. Never have gotten it while driving.
I put a meter on the battery connections under the hood while the ignition is off and I get 11.7v. Switch the ignition on, it drops a bit to 11.4v. Turn on the engine and I get roughly 14.4-5v. Seems like it would be a battery issue? Shouldn't the voltage be 12.4-5v when ignition is off? |
04-27-2018, 12:51 PM | #2 |
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How old is the battery? They are known to go through batteries every 3-4 years
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04-27-2018, 04:05 PM | #4 |
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You'll probably need a new battery.
You may be able to extend the life a bit by hooking up a ctek battery tender and charging it. see what happens
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04-27-2018, 07:32 PM | #5 |
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11.7v is an extreme state of discharge. Car batteries are often damaged by that low of voltage.
I’d replace it since it’s an auto battery and discharging it below 50% aka about 12v ussally damages them. |
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04-28-2018, 12:12 PM | #6 |
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Here is a picture of the battery label, which says 92ah. Most of the batteries I see at local auto stores are 95ah, so I assume I would need to register a new battery.
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04-28-2018, 09:24 PM | #8 |
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The proper way to do this test is with a lot of electrical load.
Turn on the car and switch on as many electrical items as possible. essentially inducing a heavy electrical load. -Max AC -Heated seats (front/rear) -Vented seat/active seat -High Beam -wipers -Radio Then check your volt meter. If you see the voltage starts dropping below 13v, you might have an issue with your alternator or voltage regulator. |
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04-30-2018, 06:58 AM | #9 | |
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But like I said, you have an automotive battery not a deep discharge battery. Automotive batteries have very thin/high surface area led plates which are great for short bursts of high current for starting. However the plates are easilty damaged when the battery is more than 50% discharged. Your battery has been deeply discharged and will likely need replacement Just go to autozone and have them do a battery and alternator load test. They do it for free, and will tell you exactly what’s wrong. |
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