Checking Car Battery Voltage With Multimeter

Using your multimeter you want to measure dc voltage this is indicated with a solid line and a dashed line above a letter v.

Checking car battery voltage with multimeter.

For readings that are over 12 5 volts it means that your battery is fully charged and it is in good condition. Load test a car battery using a multimeter. You can use a multimeter to find out if your battery has enough charge. How to check car battery with multimeter.

How to check a car battery with a multimeter. With the headlights on at 80 f there should be a voltage drop of at least 11 8 volts 25 charged and ideally 12 5 volts between the positive and negative terminals. How to test a car battery. To be more specific.

The first test with your multimeter will measure dc voltage indicated with a solid line and a dashed line above a letter v. The battery ratings vary a lot from car to car but choosing 15 20 volt is good enough. Touch the red probe to the positive terminal and the black probe to the negative terminal. Set the dial to 20 which will allow you to accurately measure between 0 20 volts.

Allow us to give you a piece of advice here you should keep the headlights on for a few minutes before checking the battery. At about 80 degrees a fully charged battery will be around 12 5 12 6 volts. Then proceed to check the reading on the multimeter display. Checking the voltage can be misleading because the battery may test good based on voltage but can not hold a load.

A car battery s voltage is dependent on the outside temperature so assuming it s 27 degrees celsius here s what you should make of the readings you see on the multimeter display. For your battery to pass a load test the multimeter must read between 9 5 to 10 5 volts straight for 30 seconds when the battery is tested. Connect the multimeter probes to the car battery. In modern vehicles a load test is a better way to tell if your battery is good or needs to be replaced.

The temperature outside affects the voltage of the battery. Set the dial to 20. Any reading of voltage below 9 5 volts or if the battery holds a good record for a while and steadily drops or even when it falls instantly to 0 volts then it means there is a problem and the battery.