Open the fob and remove the old battery
Most Subaru keyless fobs split into two halves held together by a small slot or seam. Look along the edge of your fob for a thin line running around the perimeter — that is where the two pieces separate. Insert a flat tool (a coin, flathead screwdriver, or the edge of a butter knife works) into the slot and gently twist to pry the fob open. Do not force it; if you meet resistance, try a different spot along the seam.
Once the fob is open, you will see a small round battery sitting in a metal holder. The battery is typically a CR2032 or CR2025 coin cell, which you can identify by the numbers printed on its surface. Note which side faces up — the positive side (marked with a plus sign) usually faces toward you. Gently pry the battery out of its holder using your fingernail or a plastic tool. Avoid touching the new battery with bare fingers, as oils from your skin can reduce its lifespan.
Key Takeaways
- Subaru fobs typically use a CR2032 or CR2025 coin cell battery, which you can buy at any drugstore, grocery store, or hardware store for under five dollars.
- The fob splits open along a seam running around its edge; use a flat tool to gently pry the two halves apart.
- Insert the new battery with the positive side (marked with a plus sign) facing up, matching the orientation of the old one.
- Test the fob before closing it completely by pressing each button to confirm the doors lock and unlock.
Insert the new battery with the correct orientation
Before you install the new battery, confirm you have the right type. Check your old battery or look up your specific Subaru model year online — most 2010 and newer Subarus use CR2032, while some older models use CR2025. Both are widely available at pharmacies, supermarkets, and auto parts stores. A single battery costs between two and five dollars.
Slide the new battery into the metal holder, making sure the positive side (the side with the plus sign) faces the same direction as the old battery did. The battery should sit flat and click into place. If it does not sit flush, remove it and flip it over — the orientation matters, and the fob will not work if the battery is installed backwards.
Test the fob before closing it
With the fob still open, press each button — lock, unlock, and panic if your model has one — and listen for a click or beep from your Subaru. You should hear the car respond or see the lights flash. If nothing happens, remove the battery, flip it over, and try again. A reversed battery is the most common reason a newly installed battery does not work.
If the fob still does not respond after trying both orientations, the battery may be defective or the fob itself may have a problem. Try a different new battery from a different package or store before assuming the fob is broken.
Close the fob and verify it works from a distance
Once the buttons respond, align the two halves of the fob and press them together firmly until you hear or feel a click. The seam should close evenly all the way around. If one side does not close flush, open it again and check that the battery is sitting flat and nothing is blocking the edges.
Walk to your car and test the fob from several feet away. Lock and unlock the doors a few times to confirm the range is normal. If the fob works at close range but not from far away, the battery may be low-quality or partially defective — try replacing it again with a battery from a different brand or store.
What to do if the fob still does not work
If you have tried two different new batteries in both orientations and the fob still does not respond, the problem is likely inside the fob itself. The circuit board may be damaged, the buttons may be worn out, or the contacts may be corroded. At this point, you have two options: take the fob to a Subaru dealership to have it repaired or replaced, or purchase a replacement fob online and have a dealership or independent locksmith program it to your car.
Dealership replacement fobs typically cost between 150 and 300 dollars, including programming. Aftermarket fobs from online retailers cost less upfront but may require additional programming fees. Before you buy a replacement, call your local Subaru dealership and ask what they charge for a new fob and programming — prices vary by location and model year.
How to avoid battery problems in the future
Subaru fob batteries typically last three to four years with normal use. You can extend battery life by avoiding extreme heat and cold, not dropping the fob, and not leaving it in direct sunlight for long periods. If you notice the fob only works at very close range, that is a sign the battery is weakening — replace it before it dies completely and leaves you unable to unlock your car.
Keep a spare fob in your home or with a trusted person so you have a backup if your primary fob fails. If you only have one fob, consider buying a second one and having it programmed at the dealership. The cost is lower than an emergency locksmith call, and you will always have a working way to access your car.
Frequently Asked Questions
Can I use a different battery type if I cannot find CR2032 or CR2025?
No. These fobs are designed for specific battery sizes and voltages. Using the wrong battery can damage the circuit board or cause the fob to malfunction. Stick with CR2032 or CR2025 depending on your model. Both are common and available at nearly every store that sells batteries.
How do I know if my Subaru uses CR2032 or CR2025?
The easiest way is to look at your old battery after you remove it — the model number is printed on the surface. If you do not have the old battery, search online for your specific Subaru model year and "fob battery type." You can also call your Subaru dealership and give them your vehicle identification number (VIN); they will tell you which battery your fob uses.
What if I accidentally touched the new battery with my fingers?
A small amount of skin oil will not ruin the battery, but it can shorten its lifespan slightly. If you touched it, wipe it gently on a clean, dry cloth before installing it. Going forward, try to handle new batteries by the edges rather than the flat surfaces.
Can I replace the battery myself or do I need to go to a dealership?
You can replace it yourself — the process takes about five minutes and requires only a flat tool and a new battery. You do not need to go to a dealership unless the fob does not work after you install a new battery, which suggests a problem with the fob itself rather than just the battery.
How long does a new battery last?
A new CR2032 or CR2025 battery typically lasts three to four years in a Subaru fob with normal use. Heavy use or extreme temperatures can shorten that lifespan. If you use your fob frequently, you may need to replace the battery every two to three years.