A dead car battery can cause delays and frustration.
If you notice dim headlights or strange odors, it could be a sign of battery failure. In such cases, you should head to a repair shop for a battery replacement ASAP.
Want to find out the steps of a successful car battery swap?
Keep reading to explore how to change a car battery and the tell-tale signs of a weak one so you can act quickly. We’ll also discuss some roadblocks that might occur during replacement and their quick fixes.
This Article Contains:
- How to Change a Car Battery Step-By-Step
- 3 Common Car Battery Replacement Issues and Practical Fixes
- How to Choose the Right Battery for Your Car
- How to Know Your Car Battery Needs Replacement
- Can You Replace the Car Battery Yourself?
How to Change a Car Battery Step-By-Step
Changing car batteries can be daunting, especially without the right tools and repair experience. So, it’s best to leave car battery replacement to a professional mechanic.
Before starting, your mechanic will collect the following tools:
- Wrench to unfasten bolts on the battery terminals
- Ratchet set for loosening or tightening the battery clamp and terminals
- Safety goggles and hand gloves for protection against battery acid
- Wire brush to remove battery terminal corrosion
Once your mechanic has everything they need, they’ll begin changing the dead car battery:
Step 1: Park the Vehicle
The mechanic will park your car on a level surface and engage the emergency parking brake before they begin changing the old car battery. If the car is parked on an inclined surface, they’ll place wooden blocks behind the tires. If it’s parked in a garage, they’ll leave the door open.
Next, they’ll wait a few minutes after turning off the car. This allows residual electrical energy to dissipate, reducing the risk of shock during battery replacement.
Step 2: Locate the Battery
They’ll open the hood to access the battery.
In most vehicles, the battery is mounted near the engine bay, but in some models, it may be in the trunk, under a seat, or behind a panel. They will also check for any covers or brackets securing the battery before proceeding with removal.
Step 3: Disconnect the Car Battery Terminals
To disconnect the battery, the mechanic will first disconnect the negative battery terminal using a socket wrench. Then, they’ll detach the positive battery terminal.
Usually, the positive terminal has a red cover and is marked with a plus (+) sign. The negative battery terminal is often black and marked with a minus (-) sign.
Step 4: Remove the Old Battery
Your mechanic will use a socket extension to remove the clamp that holds the battery to the battery tray. Since there might be more than one clamp, they’ll carefully inspect the outside of the battery to ensure all clamps have been removed.
After removing and setting the clamps aside, they’ll remove the old battery by lifting it out from its tray.
They’ll also use a bowl to collect all bolts and screws that may come out as they change the old car battery. This will ensure nothing falls into the engine bay throughout the replacement process.
Step 5: Clean the Car Battery Terminal
Next, the mechanic will clean the corrosion (greenish-grey residue) on the battery terminals with a baking soda solution. Once done, they’ll let the terminals dry completely before proceeding with the next steps.
Step 6: Install the New Battery
Your mechanic will install a replacement battery that fits your car’s requirements by referring to your car owner’s manual.
They’ll remove the red and black plastic covers from the ends of the battery post on the new car battery and place anti-corrosion washers on both posts. They’ll also spray the battery’s terminal ends with an anti-corrosion solution.
Next, the mechanic will place the new battery in the battery tray and secure it with the battery clamp.
Step 7: Attach the Battery Cables to the New Battery
The mechanic will first connect the positive cable to the positive battery post, followed by the negative battery terminal.
They’ll then check the cable tightness and try moving the new car battery to ensure secure connections. If it shifts, they’ll tighten the terminal clamps and then reinstall the battery cover.
NOTE: Changing the battery of electric vehicles is an entirely different process. Instead of simply unclamping and disconnecting low-voltage leads, replacing the battery of electric vehicles involves safely disconnecting high-voltage wiring, removing individual battery modules, and recalibrating the battery management system.
While the battery replacement steps seem straightforward, they’re not always simple. Your mechanic may encounter a few roadblocks along the way.
Keep reading to learn more.
3 Common Car Battery Replacement Issues and Practical Fixes
These are some common issues that may arise while changing car batteries:
- Stuck battery: Corrosion can cause the battery to become stuck, making removal difficult. In such cases, gently rocking the battery back and forth can help loosen it. If it doesn’t budge, the mechanic might use a battery terminal puller and apply a rust penetrant.
- Heavily corroded terminals: Rust can make it difficult for battery terminals to reconnect. Your mechanic will use a wire brush and a baking soda solution to clean the corrosion on the battery tray as well as the terminals.
- The car doesn’t start: If your car doesn’t start even after installing a new battery, your mechanic will re-check the terminal connections and confirm whether the battery is fully charged. If the problem persists, it could indicate an issue with the alternator or some other electrical system, requiring further diagnosis.
Next, let’s review the key considerations for choosing a battery for your vehicle.
How to Choose the Right Battery for Your Car
Here are a few factors to consider while purchasing a replacement battery at the auto parts store:
- Choose the suitable battery type: Depending upon your car’s make and model, you can go for:
- Flooded lead-acid batteries: These car batteries use liquid electrolytes in a hard case and are compatible with vehicles having standard power needs.
- AGM (Absorbed Glass Mat) batteries: These batteries use fiberglass materials to hold the electrolyte. They are spill-proof, low-maintenance, and offer higher CCA (Cold Cranking Amps). They’re ideal for modern vehicles with advanced electrical components.
- Determine the required CCA: Cold Cranking Amps indicate a battery’s ability to start your car in cold weather. Using one with less than the recommended CCA may leave you stranded. To find your vehicle’s minimum CCA:
- Check your current battery’s label (usually on the top or side)
- Refer to your vehicle owner’s manual
- Look up and confirm the CCA specifications on reputable websites
NOTE: You can choose a battery with a higher CCA than required, but never go lower than the manufacturer’s recommendation.
- Identify the right battery size: To select a replacement battery that fits inside your car, check your current battery’s label for the group size.
Wondering when you should get a new battery?
Let’s check out the signs indicating your car battery is due for a change.
How to Know Your Car Battery Needs Replacement
Watch out for these ten signs of a malfunctioning or dead battery:
- Dimming headlights
- Longer engine crank time
- Illuminated check engine light
- Car starts and then shuts down immediately
- Electrical components like door or interior lights and radio fail to turn on
- Rotten egg smell in the car, suggesting battery acid leakage
- Cracked battery case
- Swollen battery
- Missing filler caps causing electrolyte loss or contamination
- Battery doesn’t accept a charge from the battery charger
NOTE: A temporary solution for a dead or weak car battery is to recharge it using another battery as a power source. This gives the car enough power to get you to the auto parts store. Although a car battery charger is designed for this purpose, many people charge the battery using a jumper cable connected to another car instead.
Thinking of a DIY replacement?
Let’s see why it isn’t the best choice.
Can You Replace the Car Battery Yourself?
While you can change your car’s battery yourself it’s not recommended.
If you lack auto repair experience, disconnecting the battery can reset essential settings or activate warning lights. Additionally, handling a heavy battery containing corrosive acid demands careful attention.
A professional mechanic wears safety goggles to ensure secure handling, tests the charging system, and disposes of the old battery correctly. So, it’s best to let the car maintenance experts handle it.
Get a Quick Battery Replacement with AutoNation Mobile Service
A well-functioning car battery is the heartbeat of your vehicle — it sparks your engine to life and powers all the critical systems that keep you safe on the road.
But if you can’t start your car due to a dead battery, AutoNation Mobile Service has you covered!
Our mobile mechanics are available seven days a week and can drop by to replace your car’s old battery with a new one right from your driveway.
With convenient online booking, you can schedule an appointment for car battery replacements and other car maintenance needs.