Disconnect and Reconnect the Battery

Reviewed by the Service Reset editor · Updated August 9, 2026 · How we verify
Quick referenceTools10 mm spannerTime~15 minMethodDisconnect negative terminal first

These instructions apply to the Lexus NX Mk2 (Z2) 2022-Present.
For other models, please choose your vehicle here.

Disconnecting the 12 V battery on your Lexus NX (2022–present) — for a new battery, winter storage, or work near the airbags — is simple once you know the 12 V isn’t under the bonnet. On the NX 350h hybrid and NX 450h+ plug-in it’s in the boot.

Lexus NX Mk2 — the vehicle covered in this guide.
Lexus NX Mk2. Photo by JamesYoung8167 via Wikimedia Commons, licensed CC BY-SA 4.0.

Find the 12 V Battery First

The 12 V battery is in the luggage area (under the boot floor) — the under-bonnet terminals are for jump-starting only. This 12 V battery is the one you service; never touch the orange high-voltage cabling or the traction battery.

Disconnecting Safely

  1. Switch off and make sure all electrical consumers are off.
  2. Wait about 1 minute after switching off before disconnecting.
  3. Lift the boot floor, then disconnect the negative (−) terminal first, then the positive.
  4. Working near airbags or pretensioners? Wait 90 seconds after disconnecting before such work.

Reconnecting and Re-initialising

Reconnect positive first, then negative. The NX then re-initialises a few items, mostly by driving:

  • Steering angle / driver-assist relearn as you drive straight and turn fully each way.
  • Power tailgate: if it won’t operate automatically, simply unlock the tailgate with the key/remote to re-sync it.
  • Re-enter the clock, presets and settings.

If Something Isn’t Right Afterwards

  • Steering or assist warning lights usually clear once the relearns complete after a short drive.
  • A persistent light stores a code — look it up on autodtcs.com.
  • Fit a like-for-like aux battery (the NX uses a specific type).

Frequently Asked Questions

Where is the 12 V battery on a Lexus NX (2022 on)?

In the luggage area under the boot floor — the under-bonnet terminals are only for jump-starting.

Is it safe to disconnect the 12 V on the hybrid or PHEV?

Yes — the 12 V is separate from the high-voltage system; never touch the orange HV cabling.

Which terminal first?

Negative (−) off first, reconnect it last.

What needs resetting afterwards?

Steering-angle and driver-assist relearn by driving; the power tailgate re-syncs when you unlock it with the key; plus the clock and presets.

If a warning light stays on after reconnecting, look up the code on autodtcs.com.

Independent guide — not affiliated with Lexus. Always follow your official service manual and safety precautions. Read our full disclaimer.

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