You can replace a Cadillac key fob battery yourself in about five minutes with a coin and a fresh battery
Most Cadillac key fobs use a coin-cell battery—usually a CR2032 or CR2025—that you can buy at any drugstore, grocery store, or hardware store for two to five dollars. The fob itself snaps open with a flathead screwdriver or coin, the old battery slides out, and the new one slides in. You do not need to visit a dealer or have any special tools. The whole job takes longer to find your coin than to do the work.
The exact steps depend on which Cadillac model and fob generation you have, but the principle is the same across nearly all of them: find the seam, pry gently, swap the battery, and snap it closed. This guide covers the most common Cadillac fobs from the last 15 years.
Key Takeaways
- Cadillac key fobs almost always use a CR2032 or CR2025 coin-cell battery, which costs two to five dollars and is sold at any pharmacy or grocery store.
- The fob opens by prying along the seam with a flathead screwdriver or coin—look for the thin line where the two halves meet.
- Once open, the battery sits in a small metal holder; note which side faces up before you remove it, then insert the new battery the same way.
- After inserting the new battery, press the fob halves together until they click, then test all buttons to confirm the battery is seated correctly.
- If the fob still does not work after a fresh battery, the problem is likely a worn button contact or internal damage, not the battery itself.
Identify your fob type and battery size
Before you buy a battery, confirm which type your fob uses. Most Cadillacs from 2008 onward use a CR2032 battery, which is the most common coin-cell size. Some older models and a few recent ones use a CR2025, which is slightly thinner but the same diameter. Both are widely available and cost about the same.
The easiest way to know for certain is to open the fob and look at the battery itself—the size is printed on it. If you want to know before opening it, check your owner's manual or search online for "[your Cadillac model year] key fob battery." Once you have the right size, buy one or two extras; coin-cell batteries are cheap and you may need a replacement in a few years.
Locate the seam and open the fob
Look at your key fob and find the thin line running around the edge where the two plastic halves meet. This seam is where the fob opens. On most Cadillac fobs, the seam runs horizontally across the middle, though some models have it running vertically along one side.
Insert a flathead screwdriver or the edge of a coin (a dime or penny works well) into the seam and twist gently. Do not force it—the fob is designed to pop open with light pressure. You should feel it give way after a small turn. If it does not budge after gentle pressure, try a different spot along the seam; sometimes one end opens more easily than the other. Once you feel it start to give, work your way around the seam to separate the two halves completely.
Remove the old battery and note its position
Once the fob is open, you will see the battery sitting in a small metal holder or clip. Before you touch it, look at which side is facing up—the positive side (marked with a +) should face either up or down depending on your fob design. Take a mental note or take a quick photo with your phone so you remember the orientation.
Gently pry the battery out of its holder using your fingernail or the edge of the screwdriver. The battery is not glued in, so it should come out with light pressure. Set it aside—you do not need to keep it, but do not throw it in the trash. Most pharmacies and electronics stores have a battery recycling bin near the checkout.
Insert the new battery and close the fob
Take your new CR2032 or CR2025 battery and slide it into the holder with the positive side facing the same direction as the old battery was facing. It should sit flat and click into place. If it feels loose or does not sit flush, you may have it upside down—flip it and try again.
Once the battery is seated, align the two halves of the fob and press them together firmly until you hear or feel a click. The fob should snap shut cleanly. If there is a gap or it does not feel find, open it again and check that the battery is sitting flat in its holder and not tilted.
Test the fob and troubleshoot if needed
Press each button on the fob—lock, unlock, panic, trunk, or whatever buttons yours has—and watch your Cadillac to confirm it responds. All buttons should work when ready. If the fob is still dead, open it again and check that the battery is facing the correct direction and sitting all the way down in its holder.
If a fresh battery does not fix the problem, the issue is usually worn button contacts inside the fob or internal corrosion, not the battery itself. In that case, you may need a replacement fob from a Cadillac dealer or a third-party supplier. However, most of the time a new battery solves the problem completely.
Where to buy replacement batteries
CR2032 and CR2025 batteries are sold almost everywhere: pharmacies like CVS and Walgreens, grocery stores, hardware stores like Home Depot and Lowe's, and online retailers like Amazon. A single battery costs between two and five dollars, though buying a multi-pack is often cheaper per battery. Some stores sell them in the photo section, some in the electronics aisle, and some at the checkout counter—ask a staff member if you cannot find them.
You can also order them online and have them arrive in a day or two if you prefer. Since they are inexpensive and last several years, buying a few extras to keep at home means you will not have to make a store trip the next time your fob dies.
Frequently Asked Questions
Can I use a different battery size if I cannot find a CR2032?
No. CR2032 and CR2025 are not interchangeable—they have different thicknesses and will not fit properly in the holder. A CR2025 in a CR2032 slot will rattle, and a CR2032 in a CR2025 slot will not close. Buy the correct size for your fob. If your local store does not have it, order online or try another store.
How long does a key fob battery last?
Most coin-cell batteries in key fobs last three to four years with normal use. If you use your fob frequently—pressing buttons multiple times a day—it may last two to three years. If you use it rarely, it can last five years or longer. There is no way to predict exactly when it will die, so keeping a spare battery at home is convenient.
What if my fob will not open with a screwdriver?
Try a different tool: a coin (dime or penny), a plastic spoon handle, or a plastic pry tool. Avoid metal tools that might scratch the fob. If the seam is very tight, try inserting your tool at a different spot along the edge—sometimes one end of the seam opens more easily than the other. Work slowly and do not force it, or you may crack the plastic.
Do I need to reprogram my fob after changing the battery?
No. Changing the battery does not erase any programming. Your fob will work exactly as it did before once the new battery is in and the fob is closed. If the fob does not work after a fresh battery, the problem is not programming—it is either the battery orientation, a worn button contact, or internal damage.
Can I replace the battery in my Cadillac's spare fob the same way?
Yes. Spare fobs use the same battery and open the same way as your primary fob. If you have a spare fob that has not been used in a while, the battery may be dead from sitting. Replace it using the same steps, and the spare will work again.