These instructions apply to the Infiniti Q50 (V37) 2013-2023.
For other models, please choose your vehicle here.
Disconnecting the 12 V battery on your Infiniti Q50 (V37, 2013–2023) is a straightforward job once you know where the battery lives. You’ll do it to fit a new battery, to lay the car up over winter, to work safely near the airbags or seat-belt pretensioners, or to fully isolate the electrics before other work. Done in the right order — negative off first, positive on first — the Q50 wakes up cleanly and relearns its settings within a few minutes and a short drive. If yours is the Q50 Hybrid, this guide covers only the 12 V auxiliary battery; the orange high-voltage system is sealed and must never be touched.
Where the 12 V Battery Is
On petrol Q50s the 12 V battery is in the engine compartment, under a cover you unclip to reach the terminals. On the Q50 Hybrid the 12 V auxiliary battery is instead in the boot — and the high-voltage cabling, marked by its orange sheathing, must never be disturbed. Whichever version you have, identify the posts first: the negative (−) terminal is black and earths to the body, and the positive (+) terminal is red under a hinged guard.
Getting Ready
- Turn the ignition fully off (on the hybrid, make sure it is not in READY), take the key away and close the doors.
- Switch off every consumer so there’s no electrical load on the terminals as you break the connection.
- Note your radio and infotainment settings, any head-unit security code, the clock and your paired devices.
- Wait a couple of minutes for the control modules to power down before loosening anything.
- Have the right spanner, gloves and eye protection to hand before you begin.
Disconnecting
- Confirm the ignition is off (not READY on the hybrid) and all consumers are switched off.
- Expose the battery — under the bonnet on petrol cars, in the boot on the hybrid — and loosen the clamp on the negative (−) terminal first. Lift it clear and tuck the lead away so it can’t spring back.
- Remove the positive (+) lead only if you’re taking the battery out; for most work, isolating the negative is enough.
- Near the airbags or pretensioners, wait a few minutes after disconnecting before starting.
Reconnecting
- Refit the positive (+) terminal first and seat the clamp fully.
- Reconnect the negative (−) terminal last, then nip both clamps up snug.
- Refit the cover or boot trim, switch on and let the car settle before starting.
What You’ll Need to Reset Afterwards
- Clock and radio — re-enter the time, presets and any security code.
- Power windows — re-initialise the one-touch/anti-pinch function using our Q50 power-window guide.
- Tyre pressure monitor — re-store the pressures from the menu or let them relearn on a short drive.
- Seat and mirror memory — re-save your preferred positions if fitted.
- Some warning lights glow briefly and clear on their own once voltage is steady and the car has been driven.
If a Warning Light Stays On or the Car Feels Off
- Re-check that both clamps are tight and seated — a loose earth is the usual cause of gremlins.
- Drive gently for ten minutes so idle, throttle and tyre pressures relearn.
- Redo the window re-initialisation if the auto-up has stopped working.
- If the battery is old or was deeply flat, suspect the battery itself before your work.
- Any light that won’t clear has stored a code — decode it on autodtcs.com.
Frequently Asked Questions
Where is the battery on an Infiniti Q50?
On petrol cars it’s in the engine compartment under a cover. On the Q50 Hybrid the 12 V auxiliary battery is in the boot, and that car also has a separate high-voltage system with orange cabling you must never touch.
Which terminal do I disconnect first?
Take the negative (−) terminal off first and reconnect it last. That prevents the live positive lead being earthed through your spanner. On reassembly the order reverses: positive on first, negative last.
What needs resetting after I reconnect?
Plan to redo the clock and radio presets, re-initialise the one-touch windows and re-store the tyre pressures. Seat and mirror memory may also need re-saving. Most settings return with a menu step or relearn themselves after a short drive.
Is the hybrid different to service?
Only in where the 12 V battery sits — the boot rather than the engine bay. The disconnect and reconnect procedure is identical. The one hard rule is that the orange high-voltage cabling is off-limits; you only ever work on the 12 V battery.
Does a new battery need coding on the Q50?
A like-for-like replacement of the same type and rating usually doesn’t need coding to drive away. Fit the correct type for your car; where stop/start uses an AGM or EFB battery, a battery-management reset helps the charging system treat the new unit as fresh.
Can I jump-start it instead of removing the battery?
Yes, if you just need to get going after a flat. Remove the battery only when you’re renewing it, storing the car long-term, or need the electrics fully isolated for other work.
To relearn the windows after reconnecting, see our Q50 power-window guide. If a warning light stays on, decode it on autodtcs.com.
Independent guide — not affiliated with Infiniti. Always follow your official service manual and safety precautions. Read our full disclaimer.