How to Replace the Battery in My Cars

by Contributing Writer; Updated June 12, 2017

General Motors General Motors car keyless entry systems allow car owners to unlock the doors on their General Motors car vehicles by pressing a button on a small key fob. The key fob is a transmitter that sends a signal to a receiver in the vehicle to unlock the doors. The transmitter is powered by a small battery inside the fob. With use over time, the battery eventually gets too low to transmit the signal thus the fob no longer works as intended. A small screwdriver is all that is needed to open the fob so that the battery can be replaced.

Under The Hood:

 How to Replace the Battery in My Cadillac CTS

Park your CTS and turn off all accessories, then turn off the ignition switch and remove the key. Install a memory-saver device according to the manufacturer's instructions. Wait at least 10 minutes after turning off the ignition switch before you disconnect the battery.

Grasp the front of the rear-seat cushion, push in and pull up on the front of the cushion. Lift the cushion up, then remove it from the car.

Remove the four nuts across the bottom of the rear seat-back. Go through the trunk and remove the four nuts across the top of the rear seat-back. Pull the seat-back forward and remove the rear shoulder belts from the belt bezels. Take note of exposed wire harnesses so you can route them correctly when you reinstall the seat-back. Remove the rear seat-back from the car.

Remove the two bolts for the cargo tie-down loops in the trunk, then disengage the four retainers holding the rear compartment sill trim plate across the front of the trunk opening. Partially remove the trunk-opening weatherstrip as needed to remove the sill trim plate.

Remove eight retainers and two nuts from the side trim panel on the passenger-side of the trunk interior. Remove the side trim panel.

Turn the handle on the negative battery cable to release the cable clamp and then remove the cable from the post. Turn the handle on the positive battery cable to release the cable clamp and then remove it from the post. Remove the vent hose.

Remove a bolt from each of the two battery hold-down retainers and remove the retainers. Remove the battery from the trunk.

Clean the battery posts and the battery clamps with the battery terminal and post cleaner. Check the vent hole position on the new battery against the position on the old battery. Move the vent-hole plug from one side of the new battery to the other, if needed, so the vent hole is on the correct side of the battery. The new battery must have a vent hole or it's the wrong one -- don't use it.

Place the new battery on the battery tray in the trunk. Make sure the battery cables are routed properly around the top of the battery so they don't get pinched. Install the battery hold-down retainers and tighten retainer bolts to 13 foot-pounds. Connect the vent hose.

Seat the positive cable terminal on the positive battery post and turn the handle to secure the clamp on the post. Seat the negative cable terminal on the negative battery post and turn the handle to secure it on the post.

Install the side trim panel. Engage the retainers and tighten the nuts to 27 inch-pounds. Install the sill trim plate and engage the retainers. Fully seat the weatherstrip around the trunk opening. Install the cargo tie-down loops and tighten the bolts to 29 foot-pounds.

Install the rear seat-back, taking care not to pinch the wire harnesses. Route the shoulder belts through the belt bezels and tighten the nuts across the top and the bottom of the seat-back to 22 foot-pounds.

Bring the rear seat cushion into the car. On the back of the seat cushion, find the center wire hook and hook it under the seat back frame. Position the seatbelt buckles through the slots on the seat cushion, then push the rear of the cushion down and rearward until it latches into place. Tug up on the front of the cushion to make sure it is securely latched.

Remove the memory saver according to the manufacturer's instructions.

Items you will need

  • Socket set

  • Ratchet

  • Battery terminal and post cleaner

  • Torque wrench

 How to Change the Battery in a Mitsubishi Lancer

Prop open the hood of your Mitsubishi Lancer.

Remove the metal bracket which holds the battery in its compartment. Use your crescent wrench or the correct size box wrench to loosen and remove the nuts that hold the bracket in place. After you’ve removed the nuts from both sides, pull the bracket off of the top of the battery. If you have a late-model Lancer, the plastic air intake also runs over the top of your battery. This can be easily removed by using your Philips screwdriver to take out the screws at the front of the intake, above the grill. After the screws are out, you should be able to slide the intake out of your way.

Unhook the negative battery cable first. On most Lancers, this terminal does not have a plastic cover. Use your crescent to loosen the nut on the clamp. If the bolt begins to turn, you may have to hold the bolt head with your pliers. After the clamp is loose, pull it off of the battery post and tuck it to the side.

Slide the plastic cover off of the positive battery terminal and loosen the clamp in the same manner as you loosened the negative. Pull the clamp off of the post and tuck the cable to the side so it does not catch on the battery.

Lift the battery out of its compartment. Remember, if it is corroded or damaged in any way, do not allow it to come into contact with your skin. Use thick gloves to handle the battery.

Clean the clamps on your battery cables using your battery post and terminal cleaning tool. Brush them until the metal appears shiny.

Place your new battery into the compartment, making sure you line up the negative post with the negative cable. The negative post on your new battery will be marked with a minus sign.

Attach the positive cable first by sliding the clamp over the post. Tighten the nut on the clamp with your wrenches. The clamp should be tight enough that you cannot move it by hand. Afterward, slide the protective plastic cover over the positive terminal.

Attach the negative cable the same way you attached the positive cable.

Replace the metal bracket on top of the battery, making sure it fits snugly around the edge of the battery, then tighten the nuts, drawing them down so the battery is completely immobilized. If you have a later-model Lancer, you will then need to reattach your air intake by sliding it back into place then fastening the screws with your Philips screwdriver.

Close the hood and start your Mitsubishi Lancer.

Items you will need

  • Crescent wrench and pliers (or proper sized box wrenches)

  • Gloves

  • Philips screwdriver (for 2008+ Lancers)

  • Battery post and terminal cleaning tool

 How to Replace a Battery in a Hyundai Elantra

Plug a 9-volt battery into the computer memory saver and insert it into the power outlet/cigarette light port. This is only required on second generation and younger models with theft-deterrent radios and internal car alarm systems; however, this procedure will not hurt any year Elantra.

Open the hood and remove and engine covers (again only applicable to later versions of the model) using a ratchet, extension and socket to access the battery.

Put on safety goggles to prevent injury to the eyes, then spray the battery terminal corrosion cleaner on the negative battery terminal clamps (both negative and positive). Follow the directions on the spray can and scrub any corrosion present off the terminal clamps with a wire brush. Even if there is no corrosion present, this step is recommended.

Use a box-end metric wrench to loosen the retaining bolt to the black-wired negative battery terminal clamp first. Once the clamp is loose enough, wiggle the negative battery terminal clamp off of the battery post.

Repeat Step 5 for the red-wired positive terminal clamp. If a metal dome cover is present covering the positive clamp and post, use a small, flat pry tool to pry off the retaining tabs on the bottom of the cover to access the clamp and post.

Remove the battery hold-down using the ratchet, a socket and the extension if necessary.

Lift the battery from the battery tray and remove it from the engine compartment.

Install the replacement battery: 24 series for first generation models and 24F series for all remaining generations.

Use the wire brush to clean the inside diameter of both negative and positive terminal clamps. If necessary, re-spray the clamps to help clean them.

Install the new battery, making sure you align the positive and negative battery posts respectively to the positive and negative cables. Replace the battery hold-down and tighten.

Connect the positive battery terminal clamp to the positive post first then tighten the clamp. Repeat for the negative terminal clamp.

Spray both the negative and positive battery terminal clamps and posts with battery terminal anti-corrosion spray. Replace the positive metal dome cover if applicable.

Replace the engine covers if applicable.

Start the car to test the battery operation then remove the computer memory saver.

Items you will need

  • 9-volt battery computer memory saver

  • Safety goggles

  • Ratchet, extension and metric socket set

  • Battery terminal corrosion cleaner spray

  • Wire brush

  • Metric box-end wrench set

  • Flat pry tool (optional)

  • 24 or 24F series replacement battery

  • Battery terminal anti-corrosion spray

 How to Change the Battery on an Infinity Key

Turn the fob so the buttons are on the bottom and the smooth back is facing up.

Slide the switch on the back to the open position and pull out the metal key.

Slide the tip of the screwdriver into the slot where the key was.

Pry open the fob with the screwdriver and remove the back panel. Remove the battery with your fingernails.

Insert the new battery and replace the back panel onto the fob.

Slide the key back into place and push the sliding switch back into the closed position.

Items you will need

  • Flat-head screwdriver

  • CR2025 battery

 How to Change the Battery on a Harley Softail

Remove the Seat

Turn off the ignition. Unscrew the seat fastener located on the top of the rear fender with a Phillips-tip screwdriver.

Loosen and remove the two large bolts located on the lower left and right undersides of the seat with a large SAE hex wrench.

Slide the seat toward the rear of the bike while lifting it up and away.

Change the Battery

Unbolt the negative battery cable with a 10-mm open-ended wrench. Do the same with the positive terminal.

Disconnect the rubber battery strap. Lift the battery out of its tray.

Install a new battery in reverse order.

Items you will need

  • Phillips-tip screwdriver

  • SAE hex wrench set

  • 10-mm open-end wrench

 How to Replace the Battery in a Harley Ultra Classic

Open the tour pack. Unscrew the seat fastener on the rear fender using a Phillips screwdriver. Push the seat as far forward as possible while lifting the rear of the seat off the frame. Use your hand to pad the hardware at the back of the seat to prevent damage to the passenger backrest pad. Pull the seat rearward when the back of the seat has cleared the tour pack. Lift the seat all of the way off the frame.

Disconnect the negative terminal of the battery, using a 10-mm open-end wrench. Perform the same task on the positive battery terminal. Loosen the hold-down clamp of the battery using a T-40 Torx. Lift the battery free from the battery box. Position a new 12-volt motorcycle battery in the battery box with the terminals facing forward toward the front of the motorcycle.

Insert and tighten the positive battery cable connection, using a 10 mm open-end wrench. Perform the same task on the negative cable. Position the battery hold-down clamp over the edge of the battery. Tighten the clamp bolt with a T-40 Torx.

Hold the seat ion position with the rear elevated and push down while pushing forward on the front of the seat to engage it in the frame. Pad the hardware on the rear of the seat and push the seat down into position. Install the retainer screw and tighten securely. Grab the seat and give it a wiggle it to make sure it is engaged with the frame.

Items you will need

  • Phillips screwdriver

  • 10mm open-ended wrench

  • T-40 Torx drive head

 How to Replace a Battery in a Subaru Remote Car Door Lock

1999 to 2004 Subaru Remotes

Turn the unit over. Remove the two small screws with a Phillips-head screwdriver.

Carefully pull apart the remote case. Lift out the old battery.

Place the new battery, positive side (+) up. Re-attach the remote case. Tighten the two Phillips-head screws.

2005 to 2007 Subaru Remotes

Insert a flat-head screwdriver into the wide end of the remote (closest to the "Lock" button).

Turn the screwdriver to open the remote case. Lift out the old battery.

Insert the new battery, with the negative side (--) facing up. Position the two halves of the remote together. Push them together to close the case.

Press the "Lock" button six times (near your vehicle) to resynchronize the remote. The remote will not function unless it's resynchronized.

Items you will need

  • Battery CR2032 (1999 to 2004)

  • Phillips-head screwdriver (2005 to 2007)

  • Battery CR2025 (2005 to 2007)

  • Flat-head screwdriver (2005 to 2007)

 How to Replace the Battery on a Harley Sportster

Removing the Battery

Remove the seat. Remove the Phillips head screw at the back of the seat. Then slide the seat backward to remove the seat.

Disconnect the strap that retains the battery cover by removing the bolt and washer on the right side of the cover. Remove both the retaining strap and the battery cover.

Lift the battery upward to obtain access to the positive and negative terminals.

Unscrew the bolts that connect the positive and negative battery cables to the battery.

Lift the battery from the motorcycle.

Installing a Battery

Slide the battery into position in the battery case.

Lift the battery to gain access to the battery terminals. Connect the positive cable (red) to the positive battery terminal (+). Connect the negative cable (black) to the negative battery terminal (-). Reinstall the bolts that connect the cables to each terminal.

Reinstall the battery cover. Slide the battery strap over the cover and reinstall the bolt and washer that secures it.

Reinstall the seat. Place the seat over the battery case and slide it forward so that the hook on the front of the seat engages the tab located directly behind the gas tank.

Reinstall the phillips head screw that secures the back of the seat.

Items you will need

  • Phillips screwdriver

  • Socket set

  • Wrench set

 How to Change the Battery in a Oldsmobile Aurora

Park the Aurora on level ground and turn the engine off. Make sure your replacement battery is suitable for the year and model of your Aurora.

Lift up on the rear-seat cushion bottom to release the clips, and then pull the seat towards the front of the vehicle to remove.

Remove the battery access cover. Remove the bolts securing the battery mounting bracket.

Loosen the locking nut for the positive (+) and negative (-) battery terminals. Lift the cables from the terminals and remove the battery.

Install the new battery. Connect the red cable to the positive (+) terminal and connect the black cable to the negative (-) terminal.

Replace the mounting bracket and tighten the screws. Replace the battery access cover and the rear-seat cushion.

Items you will need

  • Pliers

  • Socket wrench

  • AC Delco replacement battery (preferred)

 How to Change the Battery in an Audi Key

Purchase a new CR 2032 or CR 1620 battery, depending on your Audi's model and year of manufacture. You may want to check your owner's manual, just to be sure. The batteries are available at automotive stores and at Audi dealers.

Press the ridged release button located on the part of the remote control key with the three rings, and pull out the emergency key. The ridges will be located on the opposite side from the rings. Barring this, you can use a butter knife or flat-head screwdriver in the gap between the key (or mechanical) portion and the button (electronic) portion of the remote to pry them apart.

Hold the key so that the three buttons face up. You should see more ridges exposed where you've just pulled off the emergency key. Press on the ridges while pulling out the battery carrier. If you don't see the ridges, then insert the butter knife into the gap, on the side, to pry the entire lid off. You actually should be able to do this with your bare hands.

Insert a new battery into the remote control. Make sure the positive (+) symbol faces down.

Slide in the battery carrier back to its original position and reinsert the emergency key.

Drop off the old battery at the store where you bought the new one. They’ll be able to recycle it or dispose of it properly.

Items you will need

  • CR 2032 battery

  • CR 1620 battery

 How to Replace the Battery in a Lexus ES 350 FOB Key

Locate the small silver switch on the bottom of your Lexus ES350 keyless entry fob. Slide the switch all the way to the right and remove the mechanical key from the electronic fob.

Examine the keyless entry fob to locate the small groove that was revealed by removing the mechanical key. Insert the tip of the mechanical key into the groove and work it back and forth until the halves of the electronic fob separate.

Use the tip of the mechanical key to pry the old battery out of the battery compartment; insert a new CR2032 battery, making sure to observe the correct polarity. Note that the battery compartment is mounted to the back of the circuit board in the electronic fob.

Align the two halves of the electronic keyless entry fob. Use your fingers to apply gentle to moderate pressure to both halves of the fob until they snap together.

Reinsert the mechanical key into the Lexus ES350 electronic fob. Push in the mechanical key until you hear it click into place.

Items you will need

  • Replacement CR2032 battery

 How to Change a Battery in a Nissan Versa

Park your Versa on level ground and remove the key from the ignition. Open and secure the hood of the Versa.

Loosen the battery terminal connection on the negative battery post with a wrench. Remove the cable. Follow the same procedure to remove the positive battery cable.

Lift the retaining strap off the top of the battery. Pull the battery's bottom tab to lift the strap up, then move the strap out of the way. Remove the battery.

Insert the new battery into the compartment. Replace the retaining strap and snap it into place. Connect the positive battery cable. Tighten it with a wrench. Attach the negative cable. Tighten the connection with the wrench. Close the hood.

Items you will need

  • Wrench set

  • New battery

 How to Replace the Battery in a Saturn Ion

Reach the battery easily behind the headlight on the driver's side.

Take off the cable ends from the battery terminals with a battery terminal puller. Remove the negative cable first.

Lift the battery out of the compartment. Safely dispose of used battery at an auto parts store, which will often take it as a trade-in, or bring it to a recycling center.

Use a wire brush to clean the tray that holds the battery. Wipe it off with a damp cloth and let it dry before replacing new battery.

Clean the insides of the connector cables with a pointed wire brush. Keep your gloves on at all times to avoid getting acid on your hands.

Place the new battery on the battery tray. Attach the correct cable on each terminal and tighten securely with pliers or socket wrench.

Items you will need

  • New 12-volt battery

  • Battery terminal puller

  • Wire brushes

  • Socket wrench

  • Gloves

  • Old rags

 How to Replace the Battery on a Polaris Sportsman 400

Turn the ATV's handlebars completely to the right to provide access to the right-front fender. Pull the splash guard off the interior of the right-front fender to reveal the battery.

Pull the left side cover, positioned below the rider's seat, off the ATV's body to access the battery support bracket.

Unscrew the bolt at the base of the battery support bracket, using a socket wrench. Pull the bracket away and lift the battery cover off the battery.

Unscrew the battery's negative wire bolt, followed by the positive wire bolt, using a Philips screwdriver. Pull the battery out of the battery compartment through the opening on the interior of the right-front fender.

Insert a new battery into the battery compartment. Screw the positive wire bolt into place, followed by the negative wire bolt, using a Phillips screwdriver.

Reinstall the left side cover and the right fender splash covers, pushing the pins on the back of the covers into the rubber grommets on the ATV's body.

Items you will need

  • Socket wrench

  • Phillips screwdriver

  • 12-volt 14 amp-hour battery

 How to Replace a Battery in a GM Remote

Insert the tip of the screwdriver into the notch on the edge of the fob adjacent to the keyring hole.

Turn the screwdriver inside the notch to gently pry apart the halves of the fob.

Remove the battery gently. The battery holder is fragile and will not tolerate aggressive handling. Lift the edge of the battery, then slip it out of its holder.

Insert the new battery into the battery holder, then snap the fob case back together.

Items you will need

  • Flat-tip screwdriver (small)

  • Battery

About the Author

This article was written by the It Still Runs team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. To submit your questions or ideas, or to simply learn more about It Still Runs, contact us.