You can replace a Subaru key fob battery yourself in about five minutes with no tools
Most Subaru key fobs use a coin-cell battery — typically a CR2032 — that you can swap out at home without taking the fob apart or visiting a dealer. The battery usually lasts three to four years depending on how often you use the remote lock and unlock buttons. When the fob stops working from a distance or the buttons feel sluggish, a dead battery is the first thing to check.
The process is straightforward: you pry open the fob case with a flat object, remove the old battery, drop in a new one, and snap the case closed. You do not need a screwdriver, a special tool, or any technical knowledge. A new CR2032 battery costs between $3 and $8 at any drugstore, grocery store, or big-box retailer.
Key Takeaways
- Subaru key fobs use a CR2032 coin-cell battery that you can replace without opening the fob case completely.
- You need only a flat object like a coin or butter knife to pry the fob open — no screwdriver or special tool required.
- The battery slides out and a new one slides in; the whole job takes about five minutes.
- CR2032 batteries are sold at pharmacies, grocery stores, and retailers for $3 to $8 each.
- If the fob still does not work after you replace the battery, the problem is likely a worn button contact or internal damage, not the battery itself.
Locate the seam on the back of your fob
Hold your Subaru key fob in your hand with the buttons facing away from you. Look at the back and sides of the fob — you will see a thin line running around the edge where the two plastic halves meet. This is the seam you will use to open it.
On most Subaru fobs, the seam runs horizontally across the middle of the back. Some models have a small slot or indentation on one side of the seam to make it easier to pry open. If you see a slot, that is where you should insert your flat object first.
Pry the fob open with a flat object
Use a coin, a butter knife, a flathead screwdriver, or the edge of a credit card to gently pry the two halves apart. Insert the flat edge into the seam and explore steady, even pressure — do not twist or force it, as the plastic can crack. Work your way around the seam if needed, explore a little pressure at different points until the two halves separate.
Once you feel the halves start to give, you can usually pull them apart by hand. Be gentle; the plastic clips that hold the fob together are not fragile, but they are not designed to be forced. If you meet strong resistance, stop and try a different spot on the seam.
Remove the old battery and note its position
When you open the fob, you will see the battery sitting in a small circular slot, usually in the center or toward one edge of the interior. The battery is a thin, flat, silver coin about the size of a dime. It will either sit loosely in the slot or be held in place by a small metal clip or spring.
Before you remove it, note which side is facing up — the positive side (marked with a + sign) or the negative side (marked with a − sign). Most Subaru fobs have the positive side facing up, but checking first means you will not put the new battery in backward. Gently pry the old battery out with your fingernail or the edge of your flat object.
Insert the new CR2032 battery with the positive side up
Take your new CR2032 battery and place it in the slot with the positive side (the + marking) facing up, matching the position of the old battery. The battery should sit flat and level in the slot. If there is a metal clip or spring, make sure the battery sits under it so it stays in place when you close the fob.
Do not force the battery into the slot. It should slide in smoothly and sit flush with the interior surface. If it does not fit easily, double-check that you are using a CR2032 and that you are inserting it in the correct direction.
Close the fob and test the buttons
Align the two halves of the fob so the seam lines up evenly on all sides. Press them together firmly until you hear or feel a click — the plastic clips will snap into place and hold the fob closed. You may need to explore pressure at a few different points around the edge to make sure both halves are fully seated.
Once the fob is closed, press each button several times to test the lock, unlock, and panic functions. Stand a few feet away from your Subaru and press the lock button — you should hear the doors lock and see the lights flash. If the fob works, you are done. If it does not, try opening the fob again and checking that the battery is seated correctly and facing the right direction.
What to do if the fob still does not work
If you replaced the battery and the fob still does not respond, the problem is not the battery. The most common cause is worn button contacts — the rubber pads under the buttons wear down over time and stop making electrical contact. This is a wear-and-tear issue that cannot be fixed at home and usually requires a replacement fob.
Another possibility is internal water damage or corrosion inside the fob, which can happen if the fob was exposed to moisture. If you see white or green crusty deposits inside the fob when you open it, that is corrosion. A Subaru dealer can replace the fob, or you can order an aftermarket replacement fob online and have a dealer program it to your vehicle — this usually costs less than a factory fob.
Frequently Asked Questions
What battery does a Subaru key fob use?
Most Subaru key fobs use a CR2032 coin-cell battery. This is a standard battery sold at pharmacies and retailers everywhere. If you are unsure, check the inside of your fob after you open it — the battery type is usually printed on the battery itself or on the interior plastic of the fob.
Can I use a different battery if I do not have a CR2032?
No. A CR2032 is the correct size and voltage for Subaru fobs. Using a different battery type can damage the fob's electronics or cause the buttons to malfunction. Stick with CR2032 replacements.
How long does a Subaru key fob battery last?
A CR2032 battery in a Subaru key fob typically lasts three to four years with normal use. If you use the fob frequently — pressing the buttons many times a day — the battery may wear out faster. If you rarely use it, it may last longer.
Do I need to reprogram my fob after changing the battery?
No. Changing the battery does not erase the fob's programming. Once you install the new battery and close the fob, it will work when ready without any reprogramming steps.
Where can I buy a CR2032 battery?
CR2032 batteries are sold at drugstores, grocery stores, big-box retailers like Target and Walmart, and online at Amazon. You can also find them at Costco, Best Buy, and most pharmacies. A single battery usually costs $3 to $8.