These instructions apply to the Infiniti Q50 (V37) 2013-2023.
For other models, please choose your vehicle here.
When the remote on an Infiniti Q50 (V37, 2013–2023) starts working only from arm’s length, needs a second press to lock the car, or stops responding altogether, the cause is nearly always a flat coin cell inside the key. Every Q50 — from the early 2.0t and 3.7 cars through the 3.0t twin-turbo and the Q50 Hybrid — ships with the same Infiniti Intelligent Key, a proximity smart fob with a hidden mechanical blade rather than a folding flip key. That means one consistent battery and one opening method across the whole generation. Here is how to spot a dying cell, the exact battery the Q50 takes, how to change it without cracking the case, and why the car will still start even if the fob is completely dead.
How to Tell the Fob Battery Is Dying
- Shrinking range. You have to be right beside the Q50 — or press the fob against the door handle — before it locks or unlocks. This is the first and clearest sign.
- A dash warning. The Q50 shows a “Key battery low” message in the instrument-cluster display when the Intelligent Key’s cell is getting weak — a direct prompt to change it before it dies completely.
- Passive entry gets flaky. The door won’t always unlock from the request button on the handle, and the car is slower to recognise the key as you approach.
- Cold-weather dropouts. A cell that is nearly flat sags further in the cold, so the fob may work in a warm garage but fail on a frosty morning.
An Intelligent Key cell in a Q50 typically lasts two to four years. If yours is around that age and doing any of the above, fit a fresh battery before you start suspecting the receiver or the car’s 12 V battery.
The Battery You Need
The Infiniti Q50 Intelligent Key uses a single CR2032 3-volt lithium coin cell. This is the standard cell for Infiniti’s Intelligent Key across the range — note that Infiniti’s older, plain (non-proximity) remotes used the thinner CR2025, so don’t assume from another Infiniti in the household. For the Q50’s smart key it is a CR2032. It is the most common fob battery made, sold in any supermarket, pharmacy or hardware shop. Buy a good-quality branded cell; budget cells can sag under the brief high current the transmitter draws and give short range even when fresh out of the packet.
How to Change the Battery
- Release the mechanical key. Turn the fob over, slide the small black release catch to one side, and pull the emergency metal blade straight out of the body.
- Split the case. With the blade removed you’ll see a seam and a couple of small notches along the edge of the fob. Insert a small flat-blade screwdriver — wrap the tip in tape to avoid scratches — into a notch and gently twist to pop the two halves apart. It separates with light pressure; don’t force it.
- Note the orientation, then lift the cell out. Look at how the old CR2032 sits before you remove it. Take care not to touch the small circuit board, which can be damaged by static.
- Fit the new cell. On the Q50’s Intelligent Key the fresh CR2032 goes in positive (+) side facing down — the marked face sits against the fob body, not upward. Matching the orientation of the cell you removed is the safest check.
- Reassemble. Press the two halves back together until they click all the way round, make sure any rubber seal is seated, then slide the mechanical blade back in until it latches.
⚠️ Get the polarity right. A CR2032 fitted upside down won’t power the transmitter and can slowly discharge against the contacts, so always confirm the positive face is down — copy the orientation of the cell you took out.
Check It Worked
Stand back a few metres and lock, then unlock, the Q50. Full range should return straight away, and the request buttons on the door handles should respond normally as you approach. The “Key battery low” message clears once the car next reads a healthy fob — occasionally that takes a drive cycle rather than clearing the instant you close the door.
If a Fresh Cell Doesn’t Fix It
- Re-check the polarity and seating. Positive side down is the single most common mistake, and the cell must sit firmly under its clip against clean contacts.
- 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.
- Confirm the new cell is actually good. Coin cells can sit dead on a shelf for years; a known-fresh branded battery rules this out.
- Suspect the car, not the key. If passive entry and start are erratic across both keys, a weak 12 V battery in the Q50 itself can mimic key faults. If the car is slow to wake or shows other electrical gremlins, have the vehicle battery tested.
New Key or Spare — Why It’s a Dealer Job
Changing the coin cell keeps the fob’s existing coding, so nothing needs reprogramming — the key works the moment the battery is back in. Adding a new Intelligent Key is a different story: the Q50’s immobiliser and BCM have to be accessed with the correct diagnostic tool, and blank fobs must be ordered and coded against the car’s VIN. That makes a spare or a lost-key replacement a job for an Infiniti dealer or an auto-locksmith who handles Nissan/Infiniti smart keys. The cheap insurance is to keep the battery in your spare fob fresh too, so you’re never down to a single working key.
Frequently Asked Questions
What battery does an Infiniti Q50 key fob take?
A single CR2032 3-volt lithium coin cell. Every V37 Q50 uses the Intelligent Key, so the CR2032 applies right across the 2013–2023 range, including the hybrid.
Which way does the battery go in?
Positive (+) side facing down, with the marked face against the fob body. Always match the orientation of the cell you removed — an upside-down cell won’t work and can discharge itself.
Do I have to reprogram the key after changing the battery?
No. A battery swap doesn’t affect the fob’s coding, so it pairs with the car straight away. Only a brand-new key needs programming.
How long should a Q50 key battery last?
Usually two to four years. Leaving the fob sitting close to the car so it wakes repeatedly, or heavy daily use of the remote, shortens that.
Can I start the Q50 if the fob battery is completely dead?
Yes. Press the brake, then hold the fob against the ENGINE START/STOP button — the back of the fob, where the Infiniti emblem is, against the button. The car reads the key’s built-in transponder at close range; when it recognises the fob you can push the button (using the fob itself) and start normally. A dead cell won’t strand you.
How do I get into the car if the remote won’t unlock it?
Slide the black catch on the fob and pull out the hidden mechanical blade, then use it in the driver’s door lock. Once inside, the dead-fob start method above gets you moving.
If your Q50’s remote quit suddenly right after the 12 V battery was disconnected — rather than fading over weeks — the pairing or a stored electrical fault is a more likely culprit than the coin cell. You can look up any stored trouble code and what it means on autodtcs.com.
Independent guide — not affiliated with Infiniti. Always follow your official service manual and safety precautions. Read our full disclaimer.