Mazda CX-3 key fob battery
Every model year listed for the Mazda CX-3 has a proven battery. The most common answer is CR2025. Rows below run oldest to newest; a year can appear twice when the car came with more than one kind of key.
- 2016Smart key
CR2025
Owner's manual: mazdausa.com (checked Nov 1, 2026)
Manual text: “Replace only with the same type battery (CR2025 or equivalent).”
Find CR2025 on Amazon - 2017Smart key
CR2025
Owner's manual: mazdausa.com (checked Nov 1, 2026)
Manual text: “Replace only with the same type battery (CR2025 or equivalent).”
Find CR2025 on Amazon - 2018Smart key
CR2025
Owner's manual: mazdausa.com (checked Nov 1, 2026)
Manual text: “Replace only with the same type battery (CR2025 or equivalent).”
Find CR2025 on Amazon - 2019Smart key
CR2025
Owner's manual: mazdausa.com (checked Nov 1, 2026)
Manual text: “Replace only with the same type battery (CR2025 or equivalent).”
Find CR2025 on Amazon - 2020Smart key
CR2025
Owner's manual: mazdausa.com (checked Nov 1, 2026)
Manual text: “Replace only with the same type battery (CR2025 or equivalent).”
Find CR2025 on Amazon - 2021Smart key
CR2032
Owner's manual: mazdausa.com (checked Nov 1, 2026)
Manual text: “Replace only with the same type battery (CR2032 or equivalent).”
Find CR2032 on Amazon
Changing the battery
Smart key (push-button start)
- Most push-button fobs hide a metal backup key. Press or slide its catch and draw the key out first.
- The gap left by the metal key usually has a pry point. A slow twist with a thin flat tool (tape on the tip saves the plastic) opens the two halves.
- Before you take the old cell out, look at its face. Put the new cell in with the same side showing, and avoid touching both faces at once.
- Close the case until it clicks all the way round, put the metal key back, then try the buttons and a push-button start.
Mazda advanced keys usually have a knob or button that frees the auxiliary key; the cover lifts once the key is out.
A CR2025 is 20 mm across and 2.5 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.
A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.
Keep spare coin cells away from small children. A swallowed coin cell can burn the throat within hours; if it happens, go to an emergency room at once.