Maintenance
How to change a car battery safely
Replacing a battery is one of the easiest DIY jobs — if you follow the right order and safety rules.
📅 Aug 17, 2026
✔ Free guide
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The golden rule
Always disconnect the negative terminal (−) first and connect it last. This avoids sparks near the battery and shorts through the body.
Step by step
- Turn the car off and remove the key
- Identify the terminals (red = +, black = −)
- Loosen and remove the negative (−) terminal
- Remove the positive (+) terminal
- Unbolt the hold-down bracket
- Lift the battery out (use both hands, it is heavy)
- Clean the tray and terminals
- Fit the new battery and bracket
- Connect positive (+) first, then negative (−)
- Start the car to confirm
Avoid losing your settings
Many cars forget radio codes, clock and idle settings when the battery is off. A memory saver (small 9V or OBD power supply) plugged into the lighter port or OBD socket keeps them while you swap.
Questions about this guide
Never. Keep tools away from both posts at once to avoid a short. That is why you remove the negative first.
You may need to re-enter the radio code and the idle may take a few drives to relearn. Windows and windows one-touch may need re-learning too.