charges the battery while the car is on, so running the vehicle gives the alternator a chance to do its magic, juicing up your new battery.
How to do it: Turn the car on and around for about 20 minutes. In addition to charging the battery, this gives your car’s electronic control module (ECU) a chance to detect any errors.
If it doesn’t work: If you’re not able to start the car after replacing the battery—or if the car dies again shortly afterward—it’s likely that you’re actually dealing with a faulty alternator, not a dead battery. Bring your car to a mechanic for repairs or an alternator replacement (typically $550 to $500).
Why you need to reset the computer: Your car’s computer—the ECU—reads data from your vehicle while it’s in operation, and a battery replacement disrupts this process. It needs a chance to clear error codes after a new battery is connected.
How to do it: Your ECU should reset on its own while you drive the car after reconnecting the new battery. If it doesn’t, there are two more ways to perform a reset:
If you have a small wrench, use it to detach the positive battery terminal for about five to fifteen minutes and reattach it.
If you have an OBD-II scanner, use it to clear any error codes.
If it doesn’t work: If you’re not able to reset the ECU on your own, there could be a problem with the ECU itself. If you still see warning lights, a professional inspection should cost between $106 and $129.
3. Reprogram your radio presets and reset the anti-theft system
Why you need to reprogram these systems: The data that your ECU stores includes information about your favorite radio stations! These will typically be reset after you replace the battery, along with your anti-theft system.
How to do it: To set your radio presets, tune to the station you want and hold down the preset button until the screen displays your chosen number. To reset your car’s anti-theft system, consult your owner’s manual.
If it doesn’t work: If you’re unable to reprogram these systems, there may be an electrical fault or a problem with the computer. Check with a trusted mechanic.
Why you need to clean your battery terminals: Most car batteries last between three and five years, on average. You can extend your battery’s longevity with regular maintenance.
How to do it: Turn off your car, disconnect the battery, and inspect the terminals and cables visually. If you notice corrosion on the terminals:
Use an old toothbrush and a baking soda solution to scrub it away.
Wipe the terminals down and allow them to dry completely.
Apply a small amount of petroleum jelly to the terminals to lubricate and protect them.
If it doesn’t work: If you notice any problems with your battery, including an
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