Can a car battery show 12 volts and still be bad?
Yes it can be bad if it’s output is 12 volts with no load and the engine not running… Load it down and watch the voltage drop… The starter is a good load to use for measuring the output under load.. Even a new battery voltage will drop with the starter running, but the battery should easily crank the car….
At what voltage is a car battery ruined?
Why Is Discharging a Car Battery Too Far So Bad? Even though 80 percent of the capacity remains when a car battery dips to around 10.5 volts, the battery is considered to be fully discharged because taking the cycle any deeper will cause irreversible damage to the plates through excessive sulfation.
What voltage should a 12 volt car battery read?
about 12.6 to 12.8 volts
A fully charged battery will typically display a voltmeter reading of about 12.6 to 12.8 volts. If your voltmeter is showing a voltage anywhere between 12.4 and 12.8, that means your battery is in good shape. Any voltage above 12.9 volts is a good indicator that your battery has excessive voltage.
How do you know if your car battery is ruined?
5 Unmistakable Signs Your Car Battery is Failing
- Dim headlights. If your car battery is failing, it’s not going to be able to fully power your vehicle’s electrical components – including your headlights.
- Clicking sound when you turn the key.
- Slow crank.
- Needing to press on the gas pedal to start.
- Backfiring.
What should the voltage be for a car battery to start?
Check the voltage when cranking the engine, if it drops below 10 or 11 volts the battery probably needs replacing. Also check the voltage when it is running, it should be 14 volts or more. If it is not then the alternator is not charging. You can’t post conmments that contain an email address.
Why does my car battery not read 12V?
If so, you can measure its density with a hydrometer, a few $. Maybe the terminals need to be cleaned. Maybe a battery cable has broken. Maybe the alternator isn’t working and it isn’t getting a charge. Before you buy a new battery, take it in for a test. Even Walmart auto shops do this free.
What should the voltage be for a 12 volt battery?
An expert who has answered 200 questions. Re: Battery tests at 12 volts but won’t start but starts… Check the voltage when cranking the engine, if it drops below 10 or 11 volts the battery probably needs replacing. Also check the voltage when it is running, it should be 14 volts or more. If it is not then the alternator is not charging.
What happens if you clean the battery terminals?
Try Cleaning Your Battery Terminals Battery corrosion is a very common yet debilitating occurrence under the hood of your car. Too much corrosion build up will hinder the delivery of power from your battery to the rest of your vehicle, which means it could prevent you from starting your car!