Finding the location of your battery is the first step. Whilst most batteries can be found by opening the bonnet and looking in the engine bay, many modern vehicles have the battery located in the boot under the boot liner. Some vehicles may even have the battery located under the rear seat. If you're unsure of your. To ensure your safety, make sure you've turned off your ignition and remove the key (if you have one that connects into the ignition lock). Make sure the key remains removed when you reconnect the battery. Wear safety goggles and. Use the spanner, socket wrench or adjustable wrench to loosen the negative terminal. This should only take a couple of left turns. Once loosened. The positive terminal is marked with a '+' symbol and often has a black cap. The negative terminal is marked with a '-' symbol and often has a red cap. These caps will need to be. The next step is to find the spanner, socket wrench or adjustable wrench you need to remove the nut on the negative and positive terminals. In some cases, you will be able to get away with an adjustable wrench. Remember,.