How to Open a Subaru Key Fob: A Step-by-Step Guide
If your Subaru key fob stops responding — or you just need to swap out a dead battery — the first step is getting the case open without breaking anything. The process is straightforward, but it varies slightly depending on which generation of fob you have. Here's how it generally works, and what to watch for along the way.
Why You'd Need to Open a Subaru Key Fob
The most common reason is a dead or dying battery. Most Subaru key fobs use a small coin-cell battery (typically a CR2032, though some models use a CR1620 or CR1616). When your fob's range shrinks dramatically, buttons require multiple presses, or your dash shows a "key battery low" warning, it's usually time to open the fob and replace the battery.
Other reasons include:
- Reseating a loose battery that's causing intermittent issues
- Inspecting for moisture or corrosion inside the case
- Replacing a cracked shell or worn buttons
What You'll Need
- A small flathead screwdriver (jeweler's size works best)
- A replacement coin-cell battery (check your owner's manual for the exact spec — don't guess)
- A clean, flat work surface to avoid losing small parts
- Optionally, a plastic pry tool to avoid scratching the fob casing
Identifying Your Subaru Key Fob Type
Subaru has used several fob designs over the years, and the opening method differs between them. The two most common configurations are:
| Fob Type | Common On | How It Opens |
|---|---|---|
| Two-piece clamshell (older style) | Pre-2015 models | Pry apart at the seam |
| Flip key / integrated key | Many 2015–present models | Remove emergency key first, then pry |
| Smart key / proximity fob | Newer Outback, Forester, Legacy | Slide out emergency key, then open seam |
If you're not sure which type you have, look at the fob for a small mechanical key. Most modern Subaru fobs contain a hidden emergency key that slides or pops out from the bottom of the unit.
How to Open a Subaru Key Fob: General Steps
Step 1: Remove the Emergency Key (If Present)
Look for a small release tab or slider on the back or bottom of the fob. Press or slide it, then pull out the mechanical key blade. This exposes the seam where the two halves of the case meet and sometimes reveals a small slot for prying.
If your fob doesn't have an emergency key, skip this step.
Step 2: Locate the Pry Point
With the key removed, you'll usually see a small notch or gap along the seam of the fob — often near where the key blade was seated. This is your entry point.
Step 3: Carefully Split the Case 🔧
Insert a small flathead screwdriver or plastic pry tool into the notch. Twist gently rather than prying hard. Work your way around the seam in small increments. Subaru fob cases are held together by plastic clips — forcing one spot too aggressively can snap them.
Most fobs have two to four clips around the perimeter. Once you've released them, the two halves should separate cleanly.
Step 4: Note the Battery Orientation
Before touching anything, look at how the battery sits in its holder. Note which side faces up — usually the positive (+) side faces outward (away from the circuit board), but this varies. Getting it backwards is a common mistake that prevents the fob from working after reassembly.
Step 5: Remove and Replace the Battery
Pop the old battery out — sometimes it lifts out with a fingernail, sometimes you need to gently lever it with your pry tool. Avoid touching the circuit board contacts. Insert the new battery in the same orientation.
Step 6: Reassemble and Test
Align the two halves of the case and press them together until the clips snap back into place. Reinsert the emergency key blade. Test all buttons before walking away from your car.
Variables That Affect This Process
Model year matters. A 2010 Outback fob opens differently than a 2022 Outback fob. Subaru redesigned their fob housings multiple times, and even the same model can come with different fobs depending on trim level and whether it has push-button start.
Battery type matters. Using the wrong coin-cell size won't damage the fob immediately, but an incorrect fit can cause poor contact or case-closing problems. The CR2032 is the most common, but some Subaru models specifically require the thinner CR1620 or CR1616. Your owner's manual is the definitive source.
Damage risk varies with technique. Plastic fob cases become more brittle with age. An older fob that's been exposed to heat or UV may crack more easily during prying. Using a plastic trim tool instead of a metal screwdriver reduces that risk noticeably.
Programming isn't required for a battery swap. Unlike replacing the fob itself, simply changing the battery doesn't erase the key's programming. Your fob should work immediately after reassembly. If it doesn't, double-check battery orientation and that all case clips are fully seated.
When a Battery Swap Doesn't Fix It
If the fob still doesn't work after a fresh battery, the issue may be a damaged circuit board, corroded contacts, or a fob that's been deprogrammed from the vehicle. In those cases, the path forward typically involves a dealer or locksmith with programming equipment — a different process entirely from what a battery swap can address.
What that looks like in cost and complexity depends on your specific Subaru model, model year, and what caused the fob to stop functioning in the first place.
