How to Replace a Car Battery

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• The first thing to do is to check your car’s owner’s manual to find out where your battery is. Some are in the boot, most are in the front. And also, just check there’s nothing special you need to do when changing the battery. If you are in any doubt, just call an auto electrician.

Choose the right battery

• Different car models use different batteries. To make sure you get the right one, take a photo of your old battery and bring it in store.

Remove keys

• Remove the key from ignition (as when you install your new battery the central locking may automatically lock your car). Make sure all electrical equipment is turned off, including the radio, lights and air con.
• If you have a keyless car, make sure your FOB key is at least 2 meters clear of the vehicle during the entire battery change procedure.

Remove old battery

• You should always wear gloves and eye protection when changing a battery so pop those on first.
• Open the bonnet.
• Remove the plastic cover that hides the battery, if there is one.
• Use the correct spanner to remove the negative terminal first, this is BLACK, or is marked with -VE. This will break the circuit. If you were to remove the positive first and your spanner was to touch the body of the car it would ground it, and this may short out your car and damage the wiring and the battery.
• Then remove the positive terminal, this is RED, or is marked with +VE .
• Remove the clamp / brace that holds the battery in place.
• Remove old battery.

Clean or replace terminals

• Clean the terminals and clean out tray that the battery sits on. If corroded – use a wire brush to scrub or wash with a baking soda and water solution, and then rinse with water.
• If terminal clamps or cables are badly corroded, they should be replaced.

Install new battery

• Place the new battery in the tray, ensuring it sits level and that terminal posts are positioned the same as the battery.
• Replace the clamp / brace that holds the battery in place securely so that the battery cannot move in the tray.
• Apply a thin coating of high temperature grease to the posts and cable connections.
• Replace the cables, starting with the positive (RED) terminal first, then the negative (BLACK).
• Tighten the connections, but don’t over tighten.
• Once the new battery is installed, turn the car on and check that everything is working correctly.
• You may need to drive it around the block to ensure all lights on the dash go off.
• Recycle your old battery.