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 DS 3 Crossback Mk1 (D34) 2019-Present.
For other models, please choose your vehicle here.

Disconnecting the 12 V battery on your DS 3 Crossback (2019–present) — to fit a new one, store the car, or work safely near the airbags — needs one PSA-specific precaution: the car’s electronics must “go to sleep” first. Here’s the safe sequence, including the electric E-Tense.

DS 3 Crossback Mk1 — the vehicle covered in this guide.
DS 3 Crossback Mk1. Photo by Vauxford via Wikimedia Commons, licensed CC BY-SA 4.0.

Before You Disconnect

The 12 V battery sits in the engine bay. On the E-Tense electric model this 12 V battery is still the one you service — never touch the orange high-voltage cabling or the traction battery.

  1. Switch the ignition off, close all the windows, and remove the key from the car (and step away so keyless access doesn’t wake it).
  2. Wait about 4 minutes for the BSI (the car’s electronic control unit) to power down fully — disconnecting before it sleeps can cause faults.
  3. Disconnect the negative (−) terminal first, then the positive.

Working near airbags or pretensioners? Allow a couple of minutes after disconnecting before starting.

Reconnecting and Re-initialising

  1. Reconnect positive first, then negative.
  2. Wait about 2 minutes before switching on, then start the car.
  3. Re-initialise the electric windows (one-touch is lost when the battery is disconnected).
  4. Re-enter the clock and any lost settings.

If Something Isn’t Right Afterwards

  • Windows only move while held — 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).
  • A new or different battery benefits from being registered with PSA equipment so the smart charging works, though it isn’t essential for a like-for-like swap.

Frequently Asked Questions

Where is the battery on a DS 3 Crossback?

In the engine bay — including on the E-Tense, where you service the 12 V battery, never the high-voltage system.

Why wait 4 minutes before disconnecting?

It lets the BSI control unit power down; disconnecting too soon can trigger electronic faults.

Which terminal first?

Negative (−) off first, and reconnect it last.

What needs resetting afterwards?

The electric windows re-initialise, plus the clock and any personal settings.

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

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

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