This Tip describes the correct procedure for changing a car battery.These steps apply equally if you intend to remove your old battery for recharging and then replacing it into the vehicle. Changing a battery is a straightforward process as long as you adhere to the correct procedure. This Tip includes some photos to help aid the process.Common cautions to be aware of before commencing;
Rubber gloves and protective eye goggles should be worn during this procedure as car batteries contain a sulfuric acid electrolyte solution. This is highly corrosive (i.e. can burn your skin) and produces a flammable gas. Do not smoke and keep naked flames away from the work area. Do not touch any old corrosion on the terminals with bare skin. Be careful when handling car batteries - they are heavy - always keep them reasonably level when handling them to prevent any acid spillage occurring
. Battery terminals contain lead - always wash your hands after completing this procedure.Caution 2:
Be careful not to cross over the connections to the battery. Red (+) is positive and goes to the
(+) Terminal on the battery. Black (-) is negative and goes to the
(-) Terminal on the battery.
- When removing the battery - always remove Negative Terminal first.
- When replacing the battery always replace Positive Terminal first.
Modern vehicles will have a number of presets that depend on a connection to the battery e.g. stereo, electric seat memory, Sat Nav
. etc... For this reason it is recommended to use a memory keeper to avoid any complications that may arise from disconnecting your old battery. A memory keeper simply plugs in to your vehicles cigarette lighter or accessory socket and maintains power to the vehicles accessories whilst you disconnect your old battery. Memory keepers can be powered by the mains supply or some require another 12v battery or 9v battery as a power source - so be sure to purchase one that suits your needs.
perform this procedure without a memory keeper but please ensure that you have all the relevant security codes you need in order to reactivate your stereo or any other accessories that will require a PIN code. If in doubt refer to your vehicles handbook.
1) Gather together the tools you need for the job.
- Your new battery which meets the specification of your vehicle.
- Wrenches/Spanners for loosening and tightening the nuts on the terminal clamps.
- A wire brush and sandpaper.
- Memory Keeper (as described).
- Vaseline or Battery Lithium grease.
2) Make sure the vehicle is parked on level ground and secured by the handbrake.
yourself with the instructions with your memory keeper and then plug it in to the cigarette lighter socket.
4) From under the hood identify the battery terminals and clamps. The negative terminal (or battery post) on top of the battery will have a minus
(-) sign beside it and the positiive terminal will have a plus
(+) sign. In addition to labelling (like on the battery below) these signs will also be indented into the plastic on the top of the battery beside the battery posts.
5) Remove the negative terminal clamp first
- using your wrenches loosen the nut (circled below in red) and remove the negative terminal clamp. Removing the negative terminal first helps to avoid any short circuit occurring
during the procedure. See below an example of a negative clamp with identification marks circled in black.
6) Next remove the positive terminal clamp.
7) There will be a battery locking mechanism holding the battery in place and clamping it to the vehicle - usually a metal bar. Remove this and then carefully remove the old battery.
8) Next clean the terminal clamps and the battery tray using the wire brush. You may also use some fine sandpaper to clean the inside of the clamps. Make sure you are wearing the safety gloves and goggles during this procedure. Remove as much corrosion and dirt as you can. This helps ensure a good connection to the new battery when you reconnect.
9) Put your new battery in and secure it to the vehicle with the locking mechanism.
the battery by attaching the Positive terminal first
and tighten the clamp with your wrench until you have a good tight connection.
11) Reconnect the Negative Terminal and secure as above.
12) Once the connections are made, you may coat the terminals with ordinary Vaseline or Battery Lithium grease to help prevent further corrosion.
13) Remove memory keeper from cigarette lighter socket. Shut the hood and the job is done.
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