These instructions apply to the Peugeot 5008 Mk2 (P87) 2017-Present.
For other models, please choose your vehicle here.
When the remote on a Peugeot 5008 Mk2 (P87, 2017–present) makes you stand right next to the car to lock it, or the dash asks you to hold the fob against the START button, the coin cell inside the key is almost always flat. This second-generation 5008 — built on the Stellantis EMP2 platform — shipped with two different keys depending on trim: a folding “flip” remote on lower-spec cars and the keyless proximity (Keyless Entry & Start) fob higher up the range. They open in a similar way but they do not take the same battery, so the first job is always to find out which key you are holding. Here is how to tell a dying cell from a real fault, the exact battery each key needs, and why cutting a brand-new key is the one part you can’t finish at home.
How to Tell the Fob Battery Is Dying
- Shrinking range. You have to be almost touching the car for the doors to respond — the classic first sign of a tired cell.
- “Hold the key to the START button.” On keyless 5008s, when the proximity fob is too weak to be read from the cabin, the car falls back to reading the transponder up close and displays a prompt to hold the fob against the start button. That is a low-battery symptom, not a fault.
- A key-battery warning in the cluster. The instrument display shows a low key-battery message when the proximity fob voltage drops.
- The flip key’s buttons stop flashing. On the folding remote, the little indicator LED won’t light on a press once the cell is flat — a quick way to confirm it’s the key, not the car.
- Cold-morning dropouts. Intermittent response when it’s cold is a near-flat cell struggling at low temperature — your cue to change it soon.
A coin cell in a 5008 key typically lasts two to four years. If yours is around that age and doing any of the above, fit a fresh cell before you start suspecting the receiver or the immobiliser.
The Battery You Need
This is where the two keys differ, so check yours before buying:
- Keyless proximity fob (push-button start, no metal ignition slot) — a CR2032 3-volt lithium coin cell.
- Folding “flip” remote (blade swings out of the body) — a thinner CR1620 3-volt lithium cell.
A CR1620 is noticeably thinner than a CR2032, so the two are not interchangeable — a CR2032 won’t fit the flip key’s holder, and a CR1620 will rattle loose in the proximity fob. Both codes are printed on the cell itself, so the safest move is to open the key first and buy to match the number you find inside. Choose a good-quality branded cell; budget cells can sag under the brief high current the transmitter draws and give poor range even when “new”.
Method 1 — Keyless Proximity Fob (CR2032)
- Release the emergency blade. Slide the small catch on the fob and pull the mechanical key blade straight out of the body.
- Insert a flat plastic tool (or the emergency blade itself) into the seam the blade leaves behind and gently twist to split the two halves of the case. Work your way round rather than forcing one corner.
- Ease the old CR2032 out of its holder, noting which way up it sits before it comes free.
- Drop the new cell in the same orientation, press it fully home under its clip, then click the two halves back together.
- Slide the emergency blade back in until it latches, and test locking and unlocking from a few paces away.
Method 2 — Folding “Flip” Remote (CR1620)
- Fold the metal blade closed so the fob is easier to grip.
- Find the seam that runs around the body of the fob. If there is a small retaining screw, undo it with a fine cross-head (Phillips) driver first; most flip keys simply clip together.
- Prise the two halves apart along the seam with a thin flat tool — a plastic trim tool or a small coin wrapped in tape avoids scratching the case.
- Lift out the flat CR1620, taking note of which face points up, then seat the fresh cell exactly the same way round.
- Clip the case back together, refit the screw if there was one, and check the buttons flash and work.
⚠️ Copy the polarity of the cell you removed. A coin cell fitted the wrong way round won’t power the transmitter and can slowly discharge against the contacts — so match the orientation of the old cell exactly rather than guessing which face goes up.
Did It Work?
Stand back a few metres and lock, then unlock, the 5008. Full range should return straight away. On a keyless car, the low-key-battery message and the “hold the key to START” prompt clear once the system next reads a healthy fob — sometimes after a single drive cycle rather than the instant you close the case.
If a Fresh Cell Doesn’t Fix It
- Re-check the polarity and seating. The commonest mistake is a cell that’s upside down or not fully clipped under its contact — pop the case and confirm it matches how the old one sat.
- Wipe the contacts. A smear of finger grease or a trace of corrosion on the terminals is enough to cause dropouts; clean them with a dry cloth.
- Warning still showing? On some cars the alert only clears after the fob has been read a couple of times. Rarely, a weak car 12 V battery can mimic key faults — if the 5008 itself is slow to wake, that’s worth checking separately.
New Key or Spare — Why It’s a Dealer Job
Swapping the coin cell keeps the fob’s existing coding, so nothing needs reprogramming and the key works the moment you close the case. A new key is a different matter: the blade has to be cut to the car, and a blank proximity fob must be coded to the 5008’s immobiliser with diagnostic equipment and ordered against the VIN. That makes adding a spare or replacing a lost key a job for a Peugeot dealer or an auto-locksmith — so keep the battery in your spare fresh too, and you’re never down to a single working key.
Frequently Asked Questions
What battery does a Peugeot 5008 Mk2 key take?
It depends on the key. The keyless proximity fob uses a CR2032 3-volt lithium coin cell; the folding flip remote uses a thinner CR1620. Open the key and match the code printed on the old cell to be certain.
Are the CR2032 and CR1620 interchangeable?
No. The CR1620 is much thinner, so a CR2032 won’t fit the flip key’s holder and a CR1620 sits too loose in the proximity fob to make reliable contact. Buy the exact code your key uses.
Which way up does the cell go?
Match the orientation of the cell you take out — note which face points up before you lift the old one free, and fit the new one the same way. A cell put in upside down won’t work and can flatten itself against the contacts.
Do I need to reprogram the key after changing the battery?
No. A battery swap doesn’t touch the fob’s coding, so it pairs with the car straight away. Only a brand-new or replacement key needs programming.
How long should a 5008 key battery last?
Usually two to four years. Leaving a keyless fob sitting near the car, so it wakes and “talks” to the vehicle constantly, tends to shorten that.
Can I drive the 5008 if the fob battery is completely dead?
Yes. Use the emergency blade hidden in the fob to unlock the driver’s door, then hold the fob against the START button as you press it — the car reads the transponder directly, so a flat cell won’t strand you.
If your remote died suddenly right after the car battery was disconnected — rather than fading gradually — the cause is more likely the pairing or a stored fault than the coin cell; you can check what any logged code means on autodtcs.com.
Independent guide — not affiliated with Peugeot. Always follow your official service manual and safety precautions. Read our full disclaimer.