Replace the Key Fob Battery

Reviewed by the Service Reset editor · Updated August 22, 2026 · How we verify
Quick referenceToolsNew CR2032 cell + flat screwdriverTime~5 minMethodSplit fob case at the seam; swap CR2032; no reprogramming needed

These instructions apply to the Hyundai i20 Mk1 (PB) 2009-2014.
For other models, please choose your vehicle here.

If the remote on your Hyundai i20 Mk1 (PB, 2009–2014) has become weak — you have to stand close to lock or unlock, or it’s become unreliable — the fob’s coin cell needs replacing. The i20 key uses a CR2032 cell, and exactly how it sits depends on the key type. This guide covers both. It takes a couple of minutes with a small screwdriver.

Hyundai i20 Mk1 — the vehicle covered in this guide.
Hyundai i20 Mk1. Photo by Charles01 via Wikimedia Commons, licensed CC BY-SA 4.0.

Which Key Do You Have?

  • Early cars (up to 2010) — one-piece remote: split the case with a screwdriver. Cell sits positive side up.
  • Later cars (from 2010) — flip key: the metal blade folds out. Cell sits positive side down.

Both take a CR2032 3 V lithium coin cell.

Early Remote (up to 2010, positive up)

  1. Insert a screwdriver into the case seam and gently separate the two halves.
  2. Lift out the old CR2032 cell.
  3. Fit the new cell with the positive (+) side facing up, then refit the cases.
  4. Check the remote locks and unlocks the car.

Flip Key (from 2010, positive down)

  1. Remove the transmitter from the key body (release the blade and open the fob).
  2. Fit the new CR2032 with the positive (+) side facing down.
  3. Refit the key blade and reassemble the fob.
  4. Check the remote locks and unlocks the car.

Does It Need Programming?

No — replacing the coin cell does not affect the fob’s pairing, so the key keeps working immediately. A lost or broken key can only be ordered and programmed by a dealer with a diagnostic tool — that part is not owner-doable.

Frequently Asked Questions

What battery does the i20 Mk1 key take?

A single CR2032 3 V lithium coin cell. Mind the orientation — positive up in the early one-piece remote, positive down in the later flip key.

My remote still won’t work with a fresh cell — now what?

Re-open it and check the cell orientation and that the contacts are clean. If it’s still dead, the fob may have an internal fault and need replacing and programming by a dealer.

Can I program a spare key myself?

No — Hyundai key programming needs the dealer diagnostic tool. Only the battery swap is owner-doable.

Why does my key fold out a metal blade?

From 2010 the i20 used a flip key with an integrated blade for the door lock; earlier cars had a separate remote and key. Both just need a CR2032 swap.

For battery work, see our i20 battery disconnect/reconnect guide. For warning lights, look up the code on autodtcs.com.

Independent guide — not affiliated with Hyundai. Always follow your official service manual and safety precautions. Read our full disclaimer.

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