What you need to do to change a Ford key fob battery
Most Ford key fobs use a coin-cell battery — usually a CR2032 or CR2025 — that you can replace yourself in about two minutes without tools. The battery sits inside a plastic case that either slides apart or opens like a clamshell, depending on your fob's age and model. Once you pop it open, you lift out the old battery, drop in the new one with the positive side facing up, and snap the case closed.
You do not need to visit a dealership or a mechanic for this task. The battery costs between $3 and $8 at any pharmacy, grocery store, or hardware store. The only thing that changes the process is whether your fob splits down the middle or has a seam you can pry open — and you will know which one you have the moment you look at it.
Key Takeaways
- Ford key fobs use a CR2032 or CR2025 coin-cell battery that you can buy at any drugstore or supermarket for a few dollars.
- The case either slides open or pries open at a seam; check your fob to see which type you have before you start.
- The battery takes about two minutes to swap, and the positive side must face up when you put the new one in.
- If your fob still does not work after the battery swap, the problem is likely the fob itself, not the battery.
Finding out which type of case your fob has
Hold your key fob in your hands and look for a seam or line running around the edge. On newer Fords, you will often see a thin line down the middle of the fob — this is a slider case. On older models, the seam might run around the perimeter, and the case opens like a clamshell.
If you see a small slot or notch on the edge, that is where you insert a coin or flathead screwdriver to pry the case open. If the fob feels like it has two halves that could separate, it is probably a slider. The easiest way to know for sure is to gently try sliding one half toward the other — if it moves even a little, you have found the right direction.
Opening a slider-case key fob
For slider cases, hold the fob with one hand and use your thumb to push one half of the case toward the other. You should feel it give way after a small amount of pressure — do not force it. The two halves will separate just enough to expose the battery compartment inside.
Once the case is open, you will see the battery sitting in a small metal holder or clip. Note which side is facing up — that is the positive side, and your new battery must go in the same way. Gently lift the old battery out with your fingernail or a plastic tool (not metal, which can damage the contacts).
Opening a clamshell or pry-open key fob
If your fob has a seam running around the edge, look for a small notch or slot. Insert a coin (a penny or dime works well) or a flathead screwdriver into the slot and gently twist or pry. The case will pop open, usually with a small click.
Work slowly and test the pressure as you go — you are not trying to force the case apart, just to separate the two halves enough to access the battery. Once it opens, the battery will be visible in its holder. Remove the old battery the same way you would from a slider case: gently, using your fingernail or a plastic tool.
Installing the new battery and closing the case
Before you buy a replacement battery, check the old one for a part number — it will say CR2032, CR2025, or another code. Take the old battery with you to the store so you can match it exactly. If you cannot read the number, CR2032 is the most common battery in Ford key fobs and will work for most models.
Insert the new battery into the holder with the positive side (marked with a + symbol) facing up, the same way the old one was sitting. Press it down gently until it clicks or sits flush in the holder. Then close the case by sliding the two halves together (for slider cases) or pressing the two halves together until you hear a click (for clamshell cases).
Test the fob by pressing a button — the lights should come on, or you should hear a beep from your car. If nothing happens, the battery may not be making contact. Open the case again and make sure the battery is sitting all the way down in its holder and the positive side is facing up.
What to do if the fob still does not work
If you have replaced the battery and the fob still does not respond, the problem is not the battery. The issue is usually inside the fob itself — a broken button, corroded contacts, or a damaged circuit board. At that point, you have two options: buy a replacement fob from a Ford dealership or an aftermarket supplier, or have a locksmith program a used fob to your car.
A new OEM (original equipment manufacturer) fob from a Ford dealership costs more than an aftermarket fob, but it is may provide to work with your vehicle. Aftermarket fobs are cheaper and often work just as well, but you will need to have them programmed. Some dealerships will program a fob you bring to them; others will only program fobs they sell. Call ahead to ask.
Frequently Asked Questions
Where do I buy a replacement battery for my Ford key fob?
Any pharmacy, grocery store, or hardware store carries CR2032 and CR2025 coin-cell batteries in the watch or battery section. You can also order them online. They cost between $3 and $8 per battery, and many stores sell them in multipacks if you want extras.
Can I use a different battery size if I cannot find the exact one?
No. The battery size matters because it has to fit in the holder and make proper contact with the terminals. Using the wrong size can damage the fob or cause it to malfunction. Always match the part number on the old battery or check your vehicle's manual.
What if I drop the battery inside the fob and cannot find it?
The battery is small but magnetic, so it usually stays in the case. Tilt the fob gently and look inside with a flashlight. If it has fallen out, it will be somewhere nearby on the floor or table. Once you find it, clean it with a dry cloth before putting it back in.
Do I need to reprogram my key fob after changing the battery?
No. Changing the battery does not erase the programming. Your fob will work exactly as it did before, as long as the new battery is the correct type and installed correctly.