Car Key Fob Battery Replacement

The battery type for your key, the tools, and the four steps to change it yourself.

Most remote keys use a CR2032, CR2025 or CR2016 lithium coin cell. The model is stamped on the battery inside the fob — when the remote gets weak, replace it before the car fails to start.

How to find your battery model
  1. 01
    Read the battery

    The number on the cell (CR2032, CR2025…) is stamped clearly — always match, not guess.

  2. 02
    Open the fob

    Slide the release or pop the cover at the seam with a flat tool. Entry keys have a key release button first.

  3. 03
    Check the year

    The same model year usually uses the same battery. If unsure, take the old battery with you.

Replace it in four steps
01

Open the key shell

Use the seam notch. No seam? Many fobs have a release button for the key blade, then two shell halves.

02

Take the old cell out

Rock it out gently with a plastic tool — avoid steel that can short the contacts.

03

Note the polarity

The printed + side faces the same direction in almost every fob. Note it before removal.

04

Insert and test

Close the shell, press lock. If the car does not respond, recheck orientation and contact.

Common batteries for this brand

  • Nissan · CR2032
  • Toyota · CR2032
  • Honda · CR2025 · CR2032
  • Ford · CR2032
  • Mazda · CR2025
  • Jeep · CR2032
  • Hyundai · CR2032
  • BMW · CR2032

Model year and trim vary — the stamped number on your old battery is always the correct reference.

FAQ

How do I open a key fob?

Look for the release button or the seam notch, then separate the shell halves with a flat tool — no drilling.

Which battery does my Nissan / Toyota / Honda use?

Most models run CR2032; some Honda and Mazda remotes use CR2025. Check the stamped number to be sure.

How long does a key fob battery last?

Two to three years under normal use — earlier if the remote is used frequently.

The remote still does not work after changing the battery?

Check the cell orientation and the contact springs, then re-programme the fob if your model requires it.

Where can I buy key fob batteries in bulk?

From the factory — wholesale prices from 50 cartons, OEM label and child-resistant packs available.