Can a car start when the battery is off?
Without an adequate charge, a car battery will be too weak to start your vehicle when you turn the ignition key. Modern-day autos always are drawing a small amount of power from the battery, even when the car has been shut off. That is because certain operations in the vehicle never are supposed to stop.
Why does my car not start when I turn it off?
It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery.
What happens if you disconnect the battery and run the engine?
If you disconnect the battery and the car conks out, you don’t know if it conked out due to insufficient alternator current, or whether the resulting transients caused your ECU (the car’s computer, which controls fuel mixture, timing, and much more) to spit out bad data, shutting down the car. Nobody should EVER run your engine without a battery.
When do you know if your car battery is dead?
After that half-hour, when you are stopped at home or in a safe place, do a little test. After you turn the engine off, wait at least a minute, then start it again. Wait another minute and start it another time or two to make sure that you won’t be stranded at the gas station or wherever you go next.
It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery.
What to do if your car battery won’t start?
Even if an ammeter (current-measuring device) says the battery is good, it can still be a few volts shy of what your vehicle needs to run efficiently. When you find yourself with a car that won’t crank hard enough to start, you’ll want to use jumper cables or a jump-starter box to get it running again.
What happens to the battery when the car starts?
After a battery starts a car, the alternator takes over and powers the electrical systems of the car and also recharges the battery, which we’ll talk about next. As long as the car is being run fairly often the battery can be continuously recharged and ready for use.
If you disconnect the battery and the car conks out, you don’t know if it conked out due to insufficient alternator current, or whether the resulting transients caused your ECU (the car’s computer, which controls fuel mixture, timing, and much more) to spit out bad data, shutting down the car. Nobody should EVER run your engine without a battery.