These instructions apply to the Subaru Forester Mk5 (SK) 2019-Present. For other models, please choose your vehicle here.
Last updated:
If the key fob on your Subaru Forester (2019–present) — the SK — has lost its range or shows a low-battery message, the coin cell inside is almost certainly flat. It’s a quick swap — just check which cell yours takes.
Battery First — Two Possibilities
- Keyless ‘Access’ smart key — usually a CR2032.
- Standard remote — may use a CR1620.
HaynesPro lists both, so check the marking on the old cell before buying. If the fob is dead you can still start the car by holding it against the START button; the emergency blade unlocks the driver’s door.
Replacing the Cell
- Slide out the emergency key blade.
- Split the fob case at the seam with a small screwdriver.
- Lift out the old cell (don’t touch the terminals) and note its type/orientation.
- Fit the matching new cell (CR2032 or CR1620), correct polarity.
- Click the case back together and refit the blade.
Lost Key or Adding a Spare
A cell swap keeps the existing coding. A new key must be programmed by a Subaru dealer.
If a Fresh Cell Doesn’t Help
- Confirm the cell type and orientation.
- Hold the fob to the START button to drive in the meantime.
- Still flagging? A keyless-entry fault can store a code — look it up on autodtcs.com.
Frequently Asked Questions
What battery does the Subaru Forester key use?
A CR2032 (smart key) or CR1620 (standard remote) — check the marking on the old one.
Do I need to reprogram the key after the swap?
No — the coding is retained for a battery change.
Can I program a new Forester key myself?
No — a new key must be coded by a Subaru dealer.
The fob is dead — how do I start the car?
Hold the fob against the START button as you press it.
If the fob flagged after a battery disconnection, see our Forester battery disconnect/reconnect guide.
Disclaimer: The information on this page is provided for general guidance only. Always follow your official service manual and safety precautions when working on your vehicle. We are not responsible for errors, omissions, or any damage resulting from the use of this information.
This website is an independent resource and is not affiliated with, endorsed by, or sponsored by Subaru. All trademarks and brand names belong to their respective owners.