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Home/Land Rover/Defender/Mk2 (L663) 2020-Present/Disconnect and Reconnect the Battery

Disconnect and Reconnect the Battery

These instructions apply to the Land Rover Defender Mk2 (L663) 2020-Present. For other models, please choose your vehicle here.

Last updated: June 8, 2026

Disconnecting the 12 V battery on your Land Rover Defender (2020–present) trips a lot of owners up — it isn’t under the bonnet, it’s under one of the front seats, and there are a couple of must-do steps first or you can lock the car against yourself. Here’s the safe sequence for the L663 Defender.

Find the Battery and Prepare

The 12 V battery sits under a front seat, beneath a cover — the under-bonnet terminals are for jump-starting only.

  1. Put the gear selector in ‘P’ and release the electronic parking brake (important — once power is gone you can’t release it electrically).
  2. Turn the ignition off and check that all the doors unlock (so you’re not locked out with the power disconnected).
  3. Move the seat fully forwards and remove the battery cover.
  4. Disconnect the negative (−) terminal first, then the positive.

Working near airbags or pretensioners? Allow a minute or two after disconnecting before starting.

Reconnecting

  1. Reconnect positive first, negative last, refit the cover and the seat.
  2. Switch the ignition on and re-initialise the power windows (one-touch is lost).
  3. Re-enter the clock and settings; the air suspension may need a short drive to settle.

Fitting a new or different battery? The battery monitoring system ideally needs registering with Land Rover equipment so it charges the new battery correctly — often why stop/start stays inactive for a while afterwards.

If Something Isn’t Right Afterwards

  • Windows won’t auto-close — run the window re-initialisation.
  • Warning lights after reconnection often clear after a short drive; a persistent one stores a code (decode on autodtcs.com).
  • Parking brake or air suspension messages usually clear once you drive and the systems relearn.

Frequently Asked Questions

Where is the battery on a Land Rover Defender (2020 on)?

Under one of the front seats — slide the seat fully forward and remove the cover. The under-bonnet terminals are only for jump-starting.

Why release the parking brake first?

The electronic parking brake needs power to release — do it before disconnecting so the car isn’t stuck braked.

Which terminal first?

Negative (−) off first, reconnect it last.

What needs resetting afterwards?

The power windows re-initialise, plus the clock and presets; the BMS and air suspension relearn by driving.

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

Disclaimer: The information on this page is provided for general guidance only. Always follow your official service manual and safety precautions when working on your vehicle. We are not responsible for errors, omissions, or any damage resulting from the use of this information.

This website is an independent resource and is not affiliated with, endorsed by, or sponsored by Land Rover. All trademarks and brand names belong to their respective owners.

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Mk2 (L663) 2020-Present
  • Disconnect and Reconnect the Battery
  • Reset the Service Indicator
  • Replace the Key Fob Battery
  • Reset the Tyre Pressure Monitor (TPMS)
  • Turn Off the Start-Stop System
  • Reinitialise the Electric Windows
  • Put the Wipers in Service Position

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