These instructions apply to the Suzuki SX4 S-Cross Mk2 (AK) 2022-Present.
For other models, please choose your vehicle here.
When the remote on a Suzuki SX4 S-Cross Mk2 (2022–present) starts working only from arm’s length, needs a second press, or dies without warning, the coin cell inside it is almost always the culprit. Like its Swift and Vitara siblings, this S-Cross is sold with two different keys depending on trim — the keyless push-start smart remote that lets you unlock and start without taking the key out of your pocket, and a simpler remote-only transmitter with a fold-out mechanical blade. Crucially, the two do not take the same battery: the smart key uses a CR2032, while the remote-only transmitter uses a smaller CR1616. Below is how to tell a flat cell from a real fault, which battery your key needs, and the exact way to open each type without cracking the case.
How to Tell the Fob Battery Is Dying
- Shrinking range. You have to stand right beside the car, or almost touch the door handle with the key, before it responds. This is the earliest and most reliable sign.
- Two or three presses to lock. The car reacts intermittently rather than on the first button press — a cell that is sagging under load.
- A key-battery warning. On keyless push-start S-Cross models the instrument cluster shows a low key-battery message (and often a chime) when the smart key is running low. You may also find you have to hold the fob against the start button to get the car to recognise it.
- Cold-morning dropouts. A near-flat lithium cell loses voltage in the cold, so the key that was fine yesterday afternoon can fail on a frosty start.
A Suzuki coin cell typically lasts two to four years. If yours is past that and showing any of the above, fit a fresh battery before you start suspecting the car’s receiver or immobiliser.
The Battery You Need
Check which key you have before you buy — the two S-Cross keys take different cells:
- Keyless push-start smart key: one CR2032 3-volt lithium coin cell (the large, common one, about the size of a 5p coin).
- Remote-only transmitter (fold-out blade): one CR1616 3-volt lithium coin cell — the same 16 mm diameter but much thinner than a CR2032, so the two are not interchangeable.
If you are unsure, open the key first and read the code printed on the old cell — it will say either CR2032 or CR1616. Buy a good branded cell; cheap coin cells sag under the brief high current the transmitter draws and can give short range even when brand new.
Method 1 — Keyless Push-Start Smart Key (CR2032)
- Slide out the mechanical blade. Push the small release catch on the side of the fob and pull the emergency key blade straight out of the body.
- Split the case. Insert a coin edge or a flat-blade screwdriver wrapped in a soft cloth into the slot the blade left behind, and gently twist to pop the two halves apart. The cloth stops the plastic from scuffing.
- Discharge static first. Touch a bare metal surface with your hand before you touch the circuit board — Suzuki warns that static can damage the electronics inside the remote.
- Note how the old cell sits, then lift it out. Fit the fresh CR2032 the same way round as the one you removed; there is a “+” mark moulded inside the case to guide you.
- Click the halves back together until they seat evenly all round, then slide the mechanical blade home until it latches.
Method 2 — Remote-Only Transmitter with Fold-Out Blade (CR1616)
- Remove the retaining screw. On this key type a small cross-head (Phillips) screw holds the cover; undo it with a fine screwdriver and lift the cover off. Lift out the inner transmitter unit.
- Open the transmitter unit. Insert a flat-blade screwdriver into the slot in the edge of the unit and prise it apart gently to reach the cell.
- Discharge static first, then note the orientation of the old CR1616 before removing it.
- Fit the new cell the same way up, with its “+” face toward the “+” mark on the transmitter.
- Reassemble the unit, refit it in the key, replace the cover and drive the screw back in snugly — hand-tight only, the case is plastic.
⚠️ Match the polarity. Fitting a coin cell upside down can quietly discharge it and leave the key dead, so always copy the orientation of the cell you took out rather than guessing — and never touch both faces of the new cell with your fingers, as skin grease on the contacts causes poor connection.
Check It Worked
Stand a few metres from the car and lock, then unlock, it. Full range should return instantly. On a keyless push-start S-Cross the low key-battery message clears once the car next reads a healthy key — sometimes immediately, sometimes after one short drive. If keyless start had been temperamental, try starting the car once more to confirm it now recognises the key from your pocket.
If a Fresh Cell Doesn’t Fix It
- Re-check polarity and seating. An upside-down or loosely-seated cell is the single most common cause of a “new battery, still dead” key. Make sure it clicks firmly under its clip against clean contacts.
- Confirm the code. A CR1616 dropped into a CR2032 holder (or vice versa) will not make proper contact — double-check you fitted the correct size for your key type.
- Wipe the contacts. A dry cloth over the terminals removes finger grease or light corrosion that can cause intermittent response.
- Try the other key. If your spare works normally, the problem is the first fob itself, not the car. If neither key works and the car is slow to wake, a weak 12-volt vehicle battery can mimic key faults — worth checking before you assume the remote has failed.
New Key or Spare — Why It’s a Dealer Job
Changing the coin cell keeps the key’s existing coding, so nothing needs reprogramming and the fob works the moment the case clicks shut. Adding a new key is a different matter: the S-Cross immobiliser has to be accessed with Suzuki diagnostic equipment, and a blank smart key or transmitter must be ordered and coded against the car’s VIN. That makes a replacement or extra key a job for a Suzuki dealer or an auto-locksmith — so keep the battery in your spare fresh too, and you are never left relying on one working key.
Frequently Asked Questions
What battery does a Suzuki SX4 S-Cross Mk2 key take?
It depends on the key. The keyless push-start smart key uses a CR2032, while the simpler remote-only transmitter with the fold-out blade uses a thinner CR1616. Both are 3-volt lithium coin cells. Read the code on your old cell if you are unsure which you have.
Are the CR2032 and CR1616 interchangeable?
No. They share a 16 mm diameter but the CR2032 is much thicker. A CR1616 will rattle loose in a CR2032 holder and lose contact, and a CR2032 will not physically fit a CR1616 key. Always match the exact code.
Do I need to reprogram the key after changing the battery?
No. A battery swap does not affect the key’s coding, so it keeps working straight away. Only a brand-new key needs programming to the car.
Which way round does the cell go?
Copy the orientation of the cell you removed. Both key types have a moulded “+” mark inside to show the correct way up; fitting it reversed can flatten the cell and disable the key.
How long should the key battery last?
Usually two to four years. A keyless smart key that lives near the car and constantly wakes to look for it tends to drain faster than a remote-only transmitter you press only when needed.
Can I still get in and start the car if the key is completely dead?
Yes. Pull the mechanical blade out of the fob to unlock the driver’s door manually. On keyless models you can still start the engine by holding the dead smart key against the start button (follow the on-screen prompt), so a flat cell will not strand you.
If the remote stopped working suddenly — for example right after the car’s 12-volt battery was disconnected — rather than fading gradually, the cause is more likely a pairing or stored-fault issue than the coin cell; you can look up any related fault code on autodtcs.com.
Independent guide — not affiliated with Suzuki. Always follow your official service manual and safety precautions. Read our full disclaimer.