Replace the Key Fob Battery

Last updated: June 8, 2026

If the key fob on your Alfa Romeo 4C (2014–2018) has lost its range or the central locking has gone intermittent, the coin cell inside is almost certainly flat. It’s a quick swap with a CR2032.

Battery First — What You Need

• A CR2032 coin cell.
• A small flat screwdriver.

The 4C’s key still works mechanically with a dead fob, so you can always get in; the cell only powers the remote locking.

Replacing the Cell

1. Flip out / slide out the metal key blade.
2. Press button A and remove screw B to split the fob case.
3. Lift out the old cell (don’t touch the terminals).
4. Fit a new CR2032, observing the correct polarity.
5. Reassemble, refit the screw and close the blade.

Lost Key or Adding a Spare

A cell swap keeps the existing coding. A lost or broken key can only be ordered and coded by an Alfa Romeo dealer — there’s no owner programming sequence.

If a Fresh Cell Doesn’t Help

• Check the polarity — an upside-down cell won’t work.
• Use the key blade to lock/unlock in the meantime.
• Still intermittent? A receiver fault can store a code — look it up on autodtcs.com.

Frequently Asked Questions

What battery does the Alfa Romeo 4C key use?

A single CR2032 coin cell.

Do I need to reprogram the key after the swap?

No — the coding is retained for a battery change.

Can I program a new 4C key myself?

No — a replacement key must be ordered and coded by an Alfa Romeo dealer.

The fob is dead — can I still get in?

Yes — the metal blade unlocks the door.

For the service reminder, see our 4C service indicator reset guide.