2017–2018 Mazda Mazda3 key fob battery
The 2017–2018 Mazda Mazda3 key fob takes a CR2025, a 20 × 2.5 mm 3 V lithium cell. Below: how to open it, what to do if it dies, and the manual we checked.
Buy CR2025 batteries CR2025 specs & equivalents
Our pick: Toshiba CR2025, 2-pack on Amazon, a name-brand cell in child-resistant packaging.
Tip: change the spare key at the same time. Both cells usually age together.
Quick facts
Before you start
- Get a new CR2025 cell from a fresh pack.
- Work over a table or soft cloth so small parts and buttons don’t get lost.
- Note which way the old battery faces before you take it out.
- Keep loose coin cells away from children and pets. See coin battery safety.
How to replace the 2017–2018 Mazda Mazda3 key fob battery
- Press the release knob and slide the metal emergency key out
- Wrap the tip of a small flat screwdriver in tape and twist it in the gap to ease the cover open, then slide it along to free the cover
- Lift off the cover and the battery cap, then take out the old cell
- Fit the new CR2025 with the + side facing up and refit the cap, taking care not to damage the rubber seal
- Snap the cover back on and slide the emergency key back in
Confirmed in the 2017 and 2018 Mazda3 owner's manuals (CR2025). Mazda recommends a dealer if you are unsure. 2014-2016 manuals not available on mazdausa.com, so not included.
After you change the battery
- Press lock and unlock from a few metres away. The car should react on the first press.
- On push-button start cars, start the engine once with the fob in your pocket.
- If nothing happens, re-open the fob and check the battery direction and contacts. More fixes: key fob not working after a battery change.
About the CR2025 battery
CR2025 is a 20 mm × 2.5 mm, 3 V lithium cell with a typical capacity of about 160 mAh. The same size is sold as DL2025, ECR2025, 5003LC. A CR2012 or CR2016 has the same diameter but is thinner, so it can fit loosely and runs down sooner. Stick with CR2025.
Photos from Mazda Mazda3 owners
No owner photos yet for this generation.
Other vehicles that use a CR2025
2019–2020 Mazda CX-32016–2018 Mazda CX-32020 Mazda CX-52017–2019 Mazda CX-52016 Mazda CX-52020 Mazda CX-92016–2019 Mazda CX-92020 Mazda Mazda62016–2019 Mazda Mazda62020 Mazda MX-5 Miata2016–2019 Mazda MX-5 Miata2021–2024 Nissan Armada
Other Mazda Mazda3 years
Questions
What battery does the 2017–2018 Mazda Mazda3 key fob use?
1 × CR2025 (smart key).
How many batteries does the 2017–2018 Mazda Mazda3 key fob need?
1 CR2025 cell.
Can I use a CR2012 or CR2016 instead of a CR2025?
It has the same 20 mm diameter but is thinner, so it can lose contact and runs down sooner. Use a CR2025.
Which battery names are the same as CR2025?
DL2025, ECR2025, 5003LC are the same size as CR2025.
Do I need to reprogram the key after changing the battery?
Most key fobs keep their pairing when the battery is changed. If the fob stops working, check the battery direction and contacts first; our troubleshooting guide covers the rest.
Related guides
Fob not working after a battery change?Signs the fob battery is dyingStarting a car with a dead fobCR2032 vs CR2025 vs CR2016