Start the Car With a Dead Key Fob Battery

Last updated: June 11, 2026

Renault Arkana (2021–Present) uses Renault’s hands-free keycard with push-button start, so a dead keycard battery does not stop you driving. The starting chip inside the card is passive and needs no battery of its own, which means the engine still starts once you present the card to the START button. The Arkana has no dashboard card slot, so the dead-card method is to hold the card against the button by hand.

You will normally see a “Keycard battery low” message in the driver display before the card fully fails. Treat it as a reminder to fit a fresh cell.

Starting the Arkana with a dead keycard

1. Get into the car using the emergency key (see below) if the remote will not unlock it.
2. Sit in the driver’s seat with the keycard in hand.
3. Press the brake pedal fully and keep it held.
4. Hold the keycard flat against the START/STOP button so it makes contact.
5. Press the START button. The car’s antenna powers the card chip and the engine starts.
6. Keep the engine running until a new cell is fitted, since the car may not detect a dead card to restart it.

The Arkana is sold as a hybrid in many markets; the same card procedure applies whether the car has the E-Tech hybrid or the mild-hybrid petrol drivetrain.

Unlocking the door with the emergency key

1. Slide the catch on the keycard and pull out the integrated metal key blade.
2. The emergency lock is on the front passenger door, under a cap on the rear edge of the handle.
3. Remove the cap to expose the lock barrel.
4. Insert the blade and turn to unlock. The alarm may sound and stops once you start the car with the card.
5. Push the blade back into the card before driving.

How the keycard transponder works

The keycard contains a battery-powered radio for the remote lock and unlock buttons plus a separate, battery-free transponder chip for the immobiliser. Holding the card on the START button places that chip inside the car’s antenna field, which supplies just enough power to read its security code. That is why a dead card still starts the Arkana but can no longer lock or unlock it by remote.

Replacing the keycard battery

The Arkana card uses a single CR2032 3V coin cell.

1. Pull out the emergency key blade to release the card cover.
2. Unclip the back cover at the tab to reach the battery.
3. Remove the old CR2032 and fit the replacement, respecting the polarity shown on the cover.
4. Refit the cover and reinsert the blade.
5. Stand by the car and press a card button four times to re-sync. Slot or present the card to start, and the warning clears.

Frequently Asked Questions

Where do I hold the card on an Arkana? Flat against the START/STOP button with your foot on the brake, then press the button.

Can the emergency key start the engine? No. The blade only unlocks the door; the card must be at the START button to start.

What battery does the Arkana keycard use? A CR2032 3V lithium coin cell.

Where is the emergency door lock? On the front passenger door, under a cap on the rear edge of the handle.

Why is the “keycard battery low” message still showing after a new battery? The card needs re-syncing. Press a card button four times next to the car, then start the engine and the message clears.

If a warning light or stored fault code appears after the keycard goes flat, you can look it up on autodtcs.com.