These instructions apply to the Suzuki Swift Mk4 (A2L) 2017-Present.
For other models, please choose your vehicle here.
The Suzuki Swift (Mk4/A2L, 2017–Present) is offered with Suzuki’s keyless smart entry and a START/STOP button on SZ5 and Keyless trims, and with a remote flip key turned in an ignition barrel on lower SZ3 trims. When the smart fob’s coin cell goes flat, the lock and proximity functions die, but the immobiliser still reads the key — on push-button cars by touching the fob to the start switch, on flip-key cars via the blade in the barrel.
Start a keyless Swift Mk4 with a dead fob
If your Swift has the START/STOP button:
- 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 gear selector in neutral (manual) or P (auto).
- Hold the flat back of the smart fob directly against the START/STOP button — the button contains a short-range back-up reader for exactly this situation.
- 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 very weak cell needs the fob touching the switch.
Turn-key Swift Mk4 — the blade starts it
On an SZ3 with an ignition barrel, a flat fob disables only the remote buttons. Pull the blade from the flip key, unlock the driver’s door, slot the key into the barrel and start the car the usual way. The transponder in the key head is powered by the barrel coil, so a dead coin cell does not stop the car starting.
Unlock the Swift Mk4 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.
- The alarm may sound until you start the engine — that is expected and clears once running.
Immobiliser note
The Swift’s immobiliser reads a passive RFID transponder in the key, not the fob’s battery. On a keyless car the START/STOP button holds the back-up coil; on a turn-key car the ring around the barrel reads the chip. The car supplies the power, so the engine authorises even with a completely dead fob. A key warning that stays lit after starting suggests a real fault, not just a flat cell.
Replace the fob battery
The Swift Mk4 smart fob uses one CR2032 3V lithium coin cell. Slide out the emergency blade, then prise the two case halves apart at the seam the blade leaves — a fingernail or thin flat tool in the gap is enough. Swap the cell + side up, snap the case together and refit the blade. Remote locking and proximity entry return at once.
Frequently Asked Questions
Does my Swift Mk4 have keyless start?
SZ5 and Keyless trims do, with a START/STOP button. SZ3 cars use a flip key in an ignition barrel and need only the blade to start.
Where do I hold the fob to start a keyless Swift Mk4?
Right against the START/STOP button. This generation has no key slot or column reader — the back-up coil is inside the button.
Does the same trick work on the Swift Sport Mk4?
Yes. The Sport uses the same smart-key system and START/STOP button, so touch the fob to the button and press while holding the brake.
Which battery does the Swift Mk4 fob take?
One CR2032 coin cell. It is a common type stocked at supermarkets and hardware shops.
Why did the alarm sound when I unlocked with the blade?
Manual entry registers as a possible break-in until the transponder is verified. Starting the engine cancels the alarm.
If a 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.