These instructions apply to the Suzuki SX4 S-Cross Mk2 (AK) 2022-Present.
For other models, please choose your vehicle here.
The Suzuki SX4 S-Cross (Mk2/JY facelift, 2021–Present) ships with Suzuki’s keyless smart entry and a START/STOP button across most UK and European trims, with a built-in emergency blade in the fob. When the smart fob’s coin cell dies the remote-lock and proximity functions stop, but the immobiliser still reads the key — you start the car by holding the fob against the START/STOP button.
Start the S-Cross Mk2 with a dead fob
- Unlock and get into the car with the emergency blade first (next section), sit in the driver’s seat and close the door.
- Press and hold the brake pedal with the selector in N (manual) or P (auto).
- Hold the flat back of the smart fob directly against the START/STOP button — the button has a short-range back-up coil that reads the fob when its battery is too weak to broadcast.
- With the fob still touching the button, press the START/STOP button. The engine starts.
- If it does not catch first time, press the fob flush to the button and try again — a nearly-flat cell needs the fob touching the switch.
Unlock the S-Cross Mk2 with the emergency key blade
- Slide the release catch on the back of the smart fob and pull the metal blade out of the body.
- Insert the blade into the lock barrel in the driver’s door handle and turn to unlock. On some trims a small cap covers the barrel — lever it off with the blade tip first.
- The alarm may sound until you start the engine; running the car clears it.
Immobiliser note
The S-Cross immobiliser reads a passive RFID transponder in the key, not the fob’s battery. The START/STOP button houses the back-up reader, powered by the car, so the engine authorises even with a completely dead fob. As a self-charging hybrid, the S-Cross Mk2 also relies on a small 12V battery for the keyless and immobiliser systems — if that 12V battery is flat as well, the car will not wake regardless of the fob; jump or charge the 12V first. A key warning that stays lit after starting points to a genuine fault rather than a flat cell.
Replace the fob battery
The S-Cross Mk2 smart fob uses one CR2032 3V lithium coin cell. Slide out the emergency blade, then prise the case halves apart at the seam — a fingernail or thin flat tool in the gap is enough. Swap the cell + side up, snap the case shut and refit the blade. Remote locking and proximity entry return at once.
Frequently Asked Questions
Where do I hold the fob to start the S-Cross Mk2?
Directly against the START/STOP button. There is no key slot or column reader — the back-up coil is built into the button.
The car is a hybrid — does that change the dead-fob start?
No. The hybrid drivetrain does not affect the key system. The only difference is that the 12V battery must have charge for the keyless system to wake; if it is also flat, sort the 12V first.
Which battery does the S-Cross Mk2 fob take?
One CR2032 coin cell, sold in any supermarket or hardware shop.
Do I need a workshop tool to start it with a dead fob?
No. The fob-against-button method is a built-in owner procedure; no diagnostic tool is required.
Why did the alarm sound when I used the blade?
Manual entry registers as a possible break-in until the transponder is verified. Starting the engine cancels the alarm.
If a dashboard warning light stayed on after the no-start, look it up on autodtcs.com to confirm it was just the fob and not an immobiliser code.
Independent guide — not affiliated with Suzuki. Always follow your official service manual and safety precautions. Read our full disclaimer.