How to Change a Key Battery in a Car

Replacing the Key Battery for Screw Remotes
1. Grip the remote on either side and pull apart, separating the key from the remote. Some keys will not require this step.
2. Take a small screwdriver that fits the size and type of the screw on the back of the remote and unscrew the remote screw.
3. Use your fingernails or the screwdriver to pop out the old CR2032 battery.
4. Place the new CR2032 battery in the battery slot. Press down to ensure that it is firmly set.
5. Align the remote's plastic casing and place the screw back into the remote. Use the screwdriver to tighten the casing back together. Push the key and the remote back together.
Replacing the Key Battery for Screwless Remotes
6. Grip the remote on either side and pull apart, separating the key from the remote.
7. Locate the seam along the side of the remote. Wedge your fingernails or a small tool like a screwdriver between the seam and pull the casing apart.
8. Pop out the old battery with your fingernails or the screwdriver.
9. Place the new battery into the battery slot. Press down to secure it.
10. Align the seam on the plastic casing's sides and push together. Push the remote and the key components back together.