Subaru key fob batteries typically last three to four years before they need replacement
When your Subaru key fob stops locking or unlocking your car reliably, the battery is usually the culprit. The battery inside is a coin-cell type — most commonly a CR2032 or CR2025 — that you can replace yourself in under five minutes without tools or a trip to the dealership. The whole process costs between $3 and $8 for the battery itself.
You do not need to visit a Subaru dealer or a mechanic for this repair. The fob is designed to open from the side, and once it does, the battery slides out and a new one slides in. If your fob has stopped responding altogether, a dead battery is the most likely reason, though occasionally the fob itself needs service.
Key Takeaways
- Subaru key fob batteries are coin-cell types, usually CR2032 or CR2025, available at any pharmacy, grocery store, or hardware store for a few dollars.
- The fob case opens by sliding a small metal tab or prying gently at the seam — no screwdriver required — and the battery lifts straight out.
- When you install the new battery, the flat side faces up and the ridged side faces down, and the fob clicks shut once the battery is seated.
- If the fob still does not work after you install a fresh battery, the fob itself may need service from a Subaru dealer.
What battery type your Subaru key fob uses
Subaru key fobs from the 2000s onward use a CR2032 coin-cell battery in most models. Some older or less common fobs use a CR2025, which is slightly thinner. The easiest way to know which one you need is to look at the battery compartment itself — once you open the fob, the battery type is printed on the inside of the case.
If you want to know before you open it, you can also check your owner's manual or call a Subaru dealer with your model year and they will tell you over the phone. Both CR2032 and CR2025 batteries cost the same and are sold everywhere: pharmacies, grocery stores, dollar stores, hardware stores, and online retailers. You do not need a special automotive battery.
How to open your Subaru key fob
Subaru key fobs have a small metal tab or slot on one edge. Look along the sides of the fob for a thin line or a small notch — this is where the case splits. Slide your fingernail or a plastic spoon handle into the slot and gently pry the two halves apart. Do not use a metal screwdriver or a knife, as these can scratch the case or slip and damage the electronics inside.
Once you explore gentle pressure, the two halves will separate. The battery will be visible in a small metal holder inside. If the fob has a metal key attached, it will still be connected to one half of the case — this is normal and does not need to come apart further.
Removing the old battery and installing the new one
The battery sits in a small metal cradle with two metal tabs on either side. Lift the battery straight up and out — it should come free easily. If it is stuck, do not force it; gently wiggle it side to side as you lift.
Before you install the new battery, check which side is which. The flat side of the battery is the positive end and should face up toward the top of the fob. The ridged or bumpy side is the negative end and should face down toward the metal cradle. Slide the new battery into the cradle with the flat side up, and it will sit flush in the holder.
Closing the fob and testing it
Once the battery is seated, align the two halves of the fob and press them together firmly. You should hear or feel a small click as the case snaps shut. The fob is now closed and ready to use.
Test the fob by standing near your Subaru and pressing the lock and unlock buttons. The doors should respond when ready. If the fob works, you are done. If it still does not work after you have installed a fresh battery with the correct polarity, the fob itself may have an internal problem and will need service from a Subaru dealer.
When to replace your key fob battery before it dies completely
You do not have to wait until the fob stops working entirely. Many owners notice the buttons becoming less responsive — you have to press harder or press multiple times to lock the car — before the battery dies completely. This is a good time to replace it, because a weakening battery can leave you stranded if it fails at an inconvenient moment.
If you use your fob frequently, check the battery every two to three years. If you rarely use the remote lock feature, the battery may last longer, but coin-cell batteries do lose charge over time even when not in use. Keeping a spare CR2032 in your car or at home means you can swap it in when ready if your fob stops responding.
What to do if the fob still does not work
If you have installed a new battery with the correct polarity and the fob still does not respond, the problem is likely inside the fob itself — either a broken button contact, a cracked circuit board, or a loose connection. At this point, a Subaru dealer can inspect the fob and either repair it or replace it with a new one.
Replacement fobs from a Subaru dealer typically cost between $150 and $300 depending on your model year and whether the fob has additional features like a panic button or remote start. Some owners choose to buy aftermarket fobs online for less money, though these vary in quality and may not work with all Subaru models. If you go this route, make sure the fob is listed as compatible with your specific model year before you buy.
Frequently Asked Questions
Can I use any CR2032 battery or does it have to be a specific brand?
Any CR2032 battery will work in your Subaru key fob. Brand does not matter — Energizer, Duracell, store brands, and generic batteries all function the same way. The only thing that matters is that it is a CR2032 (or CR2025 if that is what your fob uses) and that it is fresh, not expired.
What happens if I put the battery in backwards?
If you install the battery with the ridged side facing up instead of down, the fob will not work. The fob will not be damaged, but it straightforward will not send a signal. Open the fob again, flip the battery so the flat side faces up, and close it. It should work when ready.
Do I need to reprogram my fob after I replace the battery?
No. Replacing the battery does not erase any programming. Once you install the new battery and close the fob, it will work exactly as it did before. You only need to reprogram a fob if you have lost the signal entirely or if you are pairing a new fob to your car for the first time.
How do I know if my fob battery is dying versus if the fob is broken?
A dying battery usually shows up as weak or inconsistent response — you have to press the button multiple times, or it works from very close to the car but not from far away. A broken fob typically does not respond at all, even when you press hard. Install a fresh battery first; if the fob still does not work, the fob itself likely needs service.