These instructions apply to the Opel Zafira Mk1 (T98) 1999-2005.
For other models, please choose your vehicle here.
If the remote on your Opel Zafira A (T98, 1999–2005) — sold as the Vauxhall Zafira in the UK and the Holden Zafira in Australia — only locks the car from a step away, has become hit-and-miss, or has stopped flashing altogether, the culprit is almost always the little coin cell inside the key. This first-generation Zafira shares its key design with the Astra G, Vectra and Omega of the same era: a fixed-blade, two-button remote head whose plastic case simply splits in two to reveal the battery. It is a five-minute job once you know how the case comes apart and which cell to buy. Here is how to tell a flat battery from a real fault, the exact cell you need, and why a genuinely new key is the one part you cannot sort on the driveway.
How to Tell the Fob Battery Is Dying
- Shrinking range. You find yourself standing right next to the door — or pointing the key straight at the car — before it will lock or unlock. A steadily shrinking working distance is the classic first warning.
- The button LED grows dim or stops lighting. The little red indicator on the Zafira A remote head normally winks each time you press a button. When it barely glows, or refuses to light at all, the cell voltage has dropped too low to drive the transmitter.
- You have to press two or three times. Intermittent response — especially on cold mornings, when a near-flat lithium cell loses what little punch it has left — points squarely at the battery rather than the car.
- Only the door you touch responds. If central locking is sluggish or only the driver’s door reacts, a weak fob signal is a likely cause.
A coin cell in a Zafira A remote typically lasts two to four years. If yours is older than that and showing any of these signs, fit a fresh battery before you start suspecting the receiver or the alarm.
The Battery You Need
The Zafira A two-button remote uses a single CR2032 — the flat, coin-sized 3-volt lithium cell about 20 mm across, the same one found in countless other key fobs and computer motherboards. You can buy it in any supermarket, hardware shop or petrol station. Because this key is more than twenty years old, do the sensible thing and check the marking on the cell you take out — it should read CR2032 — and match it exactly. Buy a good-quality branded cell rather than the cheapest multipack; low-grade cells sag under the brief burst of current the transmitter draws and can give poor range even when they are supposedly “new”.
How to Open the Zafira A Remote and Change the Cell
- Look for a screw first. Turn the remote head over. Most Zafira A / Astra G heads simply clip together with no fastener, but if you can see a tiny cross-head (Phillips) screw, undo it with a jeweller’s screwdriver and keep it safe — it is easy to lose.
- Find the seam. Run a fingernail around the edge of the plastic head and locate the joint where the two halves meet, usually running around the outside of the key head.
- Split the case. Insert a small flat-blade screwdriver or a thin plastic prying tool into the seam and gently twist to pop the two halves apart. Work along the seam rather than forcing one spot — you are separating the shell, not levering against the circuit board, so a little patience saves cracked plastic.
- Note how the cell sits, then lift it out. Before you touch the old battery, look at which face is uppermost and how it clips under its retaining tab. Ease it out from under the clip with a fingernail or the tip of the screwdriver.
- Fit the new CR2032 the same way round. Slide the fresh cell in under the tab in exactly the orientation the old one came out. Handle it by the edge only — grease from your fingertips across the flat faces can shorten its life.
- Clip the halves back together. Line the two shell halves up and press them until they click all the way round. Refit the screw if your key had one, then test every button.
⚠️ Get the orientation right. A coin cell fitted the wrong way up will not power the remote and can quietly drain if left in back-to-front. Do not guess — copy the exact orientation of the cell you removed, with the printed + face pointing the same way it did originally.
Did It Work?
Stand a few metres from the car and press lock, then unlock. Full range should return straight away and the button LED should flash brightly again. If the doors respond first time from across the car park, you are done. If the remote still feels weak, open the case back up and make sure the cell is seated firmly under its clip against clean metal contacts.
If a Fresh Cell Doesn’t Fix It
- Re-check the polarity and seating. An upside-down or loosely clipped cell is by far the most common reason a “new” battery changes nothing.
- Clean the contacts. On a twenty-year-old key the battery terminals and contact springs can pick up a film of dirt or light corrosion. Wipe them with a dry cloth, or a cotton bud lightly dampened with contact cleaner, and let them dry.
- Still nothing? If the LED will not light even with a known-good cell, the remote’s transmitter or button contacts may have failed after years of use — not unusual on a key this age — and the head will need repair or replacement.
New Key or Spare — Why It’s a Dealer or Locksmith Job
Swapping the coin cell leaves the remote’s existing coding untouched, so nothing needs reprogramming afterwards — the key works the moment you close the case. A new key is a very different matter. The Zafira A runs an immobiliser, and a fresh remote has to have its blade cut to your car and its transponder and remote code married to the vehicle with dedicated equipment. That makes adding a spare, or replacing a lost key, a job for a Vauxhall/Opel dealer or a good auto-locksmith working against your car’s details. The practical takeaway: keep the battery in your spare key fresh too, so you are never relying on a single working remote.
Frequently Asked Questions
What battery does an Opel/Vauxhall Zafira A key fob take?
A single CR2032 3-volt lithium coin cell. It is the standard cell for the two-button remote head shared across the Zafira A, Astra G and related models of 1999–2005. Always confirm against the code printed on the cell you remove.
How do I open the Zafira A key without breaking it?
Undo the small screw if your head has one, then work a flat screwdriver or plastic tool along the seam and twist gently to split the two halves. Ease around the whole joint rather than forcing one point, and the shell pops apart cleanly.
Do I need to reprogram the key after changing the battery?
No. A battery swap does not affect the fob’s stored code, so the remote works immediately. Only a brand-new key needs coding to the car.
Which way round does the CR2032 go?
Fit it the same way up as the cell you took out — note the orientation before you remove the old one. Getting it back-to-front simply leaves the remote dead, so match it rather than guess.
How long should a Zafira A key battery last?
Usually two to four years. Frequent locking and unlocking, or an ageing cell that has sat in a spare key for years, will shorten that.
Can I still get into and drive the car if the fob is completely dead?
Yes. The Zafira A key has a normal metal blade, so you can unlock the driver’s door and start the car by hand even with a flat remote battery — a dead cell locks you out of nothing.
If your remote quit suddenly rather than fading — particularly just after the car battery was disconnected or went flat — the fault may lie with a stored fault code or the immobiliser rather than the coin cell. You can look up what any related code means on autodtcs.com.
Independent guide — not affiliated with Opel. Always follow your official service manual and safety precautions. Read our full disclaimer.