How do you know if the battery or alternator is bad?

How do you know if the battery or alternator is bad?

Some of the things to look for are no-starting and trouble starting, dimming lights and problems with stereo system output. If your car starts but stalls when you’re underway, your battery is probably not being recharged due to a faulty alternator.

Why does my battery only show 12.4v?

12.4v is a bit low for a good battery though – should really be 12.7v, so might be that one of the cells is on the way out which of course won’t help. I see what you mean, basically a dodgy terminal connection could still show 12v at the starter but can’t deliver the ‘ampage’ when put under load?

Can a 12 volt power converter run without a battery?

Lastly, check the batteries a properly working converter should run the entire 12 volt system even without a battery (though it’s not recommended due to the tendency of converters to let transient AC voltage through, the battery acts like a “filter”).

What causes a false voltage reading on a battery?

Under the intense heat of the load, one or more of the weld pieces connecting the cells is coming loose and separating. This will cut the current, and voltage will drop. When the battery cools off, the pieces will touch, barely giving a complete connection. This gives you a false voltage reading.

What should the voltage of a motorcycle battery be?

A healthy 12 volt motorcycle battery should maintain a range from 9.5 – 10.5 volts under the load for a good 30 seconds straight. If the battery begins to hold and then steadily drops in voltage, there is a problem. If the voltage instantly drops to 0 volts,…

Why does my Car Battery Read 13 volts?

This means that your 12-volt battery can actually read as 13.2 volts instead of 12 when it is not fully charged. Most drivers never want to experience their car not starting or a bad battery. If you cannot turn on your car, let alone drive it to work or school, a bad battery, alternator, or starter are often at fault.

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?

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.

Lastly, check the batteries a properly working converter should run the entire 12 volt system even without a battery (though it’s not recommended due to the tendency of converters to let transient AC voltage through, the battery acts like a “filter”).