You will need a set of open-end box wrenches with a Ѕ” option. To remove the battery, disconnect the terminals, starting with the negative terminals first to prevent the battery from short-circuiting or a shock to you. You will need the wrench to remove the bracket bolts that secure the battery in place.
Use a voltmeter to measure the battery’s charge. This is easier with the battery out but you should still be able to check if you have left it in the car. Hold the voltmeter to the negative and positive terminals, with red on positive and black on negative terminals. The voltmeter measurement you should see is between 11 and 13 volts.
A battery that has less than 11 volts will need to be charged using a battery charger. Connect the charger’s red connector to the battery positive terminal and the black connector to the battery negative terminal. Select a charge of 20 to 40 amps on the charger. In 2 to 3 hours, your battery should be completely charged, as indicated by the status on the charger.
Conduct a load test on the battery using the voltmeter. Attach the color-coded prongs to the appropriate terminals and monitor the voltmeter display while a friend starts your car. It is important to note how long the voltage drops, and to what value. You want your car battery voltage to drop no lower than 10 volts. If your value is lower, you should replace the battery.
If your battery shows normal operation to be passed the load test, you can reinstall the battery in your vehicle. Remember, a load test that showed a voltage drop below 10 means you battery is failing so do not reinstall a bad battery. It will only give you problems down the road.