Replace the Key Fob Battery

Last updated: June 6, 2026

A weak key is the usual reason a Ford Kuga Mk3 (2020–present) stops locking from a distance or asks you to hold the fob to the start button. The Kuga came with two key styles that take different batteries, so check which you have first.

Which Battery You Need

• Keyless ‘smart’ fob (push-button start): CR2450.
• Flip / blade key: CR2032.

Open the fob and match the number on the old cell to be sure.

How to Replace the Key Battery

1. Press and hold the release and pull out the emergency blade.
2. Use the slot (or a small screwdriver) to split the fob and reach the cell.
3. Lift out the old cell, noting which way up it sits.
4. Fit the new CR2450 (smart fob) or CR2032 (flip key) the same way up.
5. Clip the fob together and refit the blade.

Lock and unlock from a few metres to confirm.

If It Still Won’t Work

• Start the car anyway — hold the fob against the start button as you press; the car reads the transponder directly.
• Lock manually with the emergency blade in the driver’s door.

Frequently Asked Questions

What battery does the Ford Kuga key take?

The keyless smart fob uses a CR2450; the flip/blade key uses a CR2032.

How do I know which one?

Open the fob and read the number printed on the old coin cell.

Do I need to reprogram the key after changing the battery?

No — only adding a brand-new key needs dealer programming.

My key still won’t start the car — what now?

Hold the fob against the start button as you press it.

For a no-start with a warning light, check the code on autodtcs.com. See also our Kuga battery guide if the car is dead.