What does 12V mean on a car battery?

What does 12V mean on a car battery?

Unless your battery is absolutely dead it will pretty much always show around the 11-12V mark when sitting idle (ignition etc off) so it’s not an indication of battery charge. When you go to turn the engine over the voltage will plummet, and you typically need at least 9V when cranking to start the engine.

Is the battery dead but showing 12V?

When jump leads are connected (showing ~14v) it will turn over fine, as it should with a fully charged battery. So is the battery dead? Or does it need some distilled water? Sure its not the starter or the wiring rather than the battery? Is the connection between the battery and the terminals good?

Why does the battery show 12.4v on the multimeter?

It is showing 12.4v using the multimeter on the terminals, it shows the same on the starter and earth point so battery connections are good. However it won’t turn the car over, it managed one really slow turn when I tried it just now. Any ideas what the problem is? In my mind 12.4v should be enough to turn over for several seconds at least.

What to do if your car wont turn over but has power?

To determine why your car won’t turn over but has power, you need to disconnect the cable from your engine and let the engine run for 30 minutes to see if the alternator can charge the battery and power the car.

Unless your battery is absolutely dead it will pretty much always show around the 11-12V mark when sitting idle (ignition etc off) so it’s not an indication of battery charge. When you go to turn the engine over the voltage will plummet, and you typically need at least 9V when cranking to start the engine.

When jump leads are connected (showing ~14v) it will turn over fine, as it should with a fully charged battery. So is the battery dead? Or does it need some distilled water? Sure its not the starter or the wiring rather than the battery? Is the connection between the battery and the terminals good?

Can a battery be cranked at 12.8 volts?

Yes, I have done the free power mod. voltage doesn’t tell you anything. only a load test will tell you if it’s any good. it doesn’t pass the test for the load your starter is putting on it. +1 what Eddie said. If you have a fully charged battery and it drops below 9V while cranking it is toast. 12.8V is not good for a fully charged battery either.

It is showing 12.4v using the multimeter on the terminals, it shows the same on the starter and earth point so battery connections are good. However it won’t turn the car over, it managed one really slow turn when I tried it just now. Any ideas what the problem is? In my mind 12.4v should be enough to turn over for several seconds at least.

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