An ohmmeter, also sometimes referred to as a volt-ohm or a multi-meter, can be used to test the voltage in your car's battery. Perhaps your headlights are flickering. Or maybe you had to jump-start your battery recently. Use an ohmmeter to measure the voltage of your battery to help you determine if you need a replacement. You can purchase an ohmmeter at any electronics store.
Turn off the engine and everything that runs on electricity; radio, lights, GPS, etc.
Open the hood of your car.
Set the ohmmeter to 25 VDC.
Touch the red or positive cable on the meter to the positive terminal on your car's battery.
Touch the negative cable on the meter to the negative terminal.
Check the meter display for the voltage reading while the meter cables are touching the battery terminals. The meter should show between 12.5 and 12.8 volts.
