These instructions apply to the Volkswagen Up Mk1 (AA) 2011-2023.
For other models, please choose your vehicle here.
Renewing a flat battery, doing bodywork or electrical work, or laying the car up for the winter on your Volkswagen Up (2011–2023)? Disconnecting the 12 V battery is one of the most common owner jobs on this car, and it is well within reach if you work in the correct order. The 12 V battery is in the engine bay. Take the negative terminal off first, refit positive first, and the Up will wake up, relearn its settings and drive normally again — no workshop visit needed for a straightforward like-for-like swap.
Where the 12 V Battery Is
Open the bonnet and the 12 V battery sits in the engine compartment. The petrol Up is a conventional car with no high-voltage system, so there is nothing hazardous to worry about — the separate battery-electric e-Up is a different vehicle and is not covered here. Look for the two terminals under their clamps: the negative (−) is the black one, usually marked with a minus sign, and the positive (+) is the red one under a flip-up cover, marked with a plus. Identifying the two correctly before you touch a spanner is the single most important step, because taking them off in the wrong order is how you cause sparks.
Before You Begin
- Switch the ignition fully off, close the doors and boot, and take the key well away from the car so nothing stays awake.
- Turn off the lights, climate fan, radio and any accessories so there is no load on the battery when you break the connection.
- If your Up plays a coded head unit, make a note of the radio security code now — you may be prompted for it once power is restored.
- Wait a couple of minutes after switching off so the control modules have time to power down before you disconnect.
- Have the correct spanner ready (a small open-ended or socket spanner fits the clamp nuts), and wear gloves and eye protection.
Disconnecting
- Switch everything off, remove the key and wait a couple of minutes.
- Slacken the negative (−, black) terminal clamp first, ease the connector off the post and tuck it aside so it cannot spring back onto the terminal.
- Release the positive (+, red) clamp only if you are removing the battery completely; for most electrical work, lifting the negative is enough to isolate the car.
Reconnecting
- Refit the positive (+, red) clamp first, then the negative (−, black) last, and tighten both firmly so there is no movement.
- Make sure nothing is left switched on, then turn the ignition on, wait a few seconds, and start the engine.
What You’ll Need to Reset Afterwards
Cutting the power wipes a few short-term memories, none of them serious. Expect to reset the clock and re-enter your radio presets (and the security code if the car uses one). The one-touch electric windows lose their auto-up/anti-pinch calibration and need re-teaching, and the tyre-pressure monitor baseline should be stored again once the tyres are at their correct pressures. Seat and mirror positions on the Up are manual, so there is nothing to relearn there. A stored service reminder is unaffected by a battery disconnect. Let the car sit for a minute after reconnecting, then take a short drive so the engine and stability systems settle.
If a Warning Light Stays On or the Car Feels Off
- Check both terminal clamps are properly tight — a loose connection is the most common cause of odd behaviour after a battery job.
- Drive gently for a few minutes; some lights self-clear once the car has relearned its idle and the systems have cycled.
- Re-do the window one-touch and, if the steering feels notchy, let the wheel sit centred with the engine running before driving.
- If the car was slow to crank or the light returns quickly, the battery itself may simply be flat or worn out rather than needing any reset.
- Read any stored fault code to see exactly what the car is flagging before assuming the worst.
Frequently Asked Questions
Where is the battery on a VW Up?
It is in the engine bay — open the bonnet and it sits in the engine compartment. It is a conventional 12 V battery with the black negative and red positive terminals under their clamps. The battery-electric e-Up is a separate model and is not covered here.
Which terminal comes off first?
Take the negative (−, black) terminal off first when disconnecting. When you reconnect, put the positive (+, red) on first and the negative on last. Following that order every time avoids sparks and short circuits.
What resets when I disconnect the battery?
The clock, radio presets and radio code, the one-touch window calibration and the tyre-pressure monitor baseline typically need re-doing. These are quick to set again and nothing is permanently lost by disconnecting the battery.
Do I need to code a new battery on a VW Up?
For a like-for-like replacement on this car, no coding is needed for normal running — fit the same type and size, connect it in the right order, and drive. There is no owner-facing battery-management registration step required on the standard petrol Up.
Will disconnecting the battery clear fault codes or the service light?
Disconnecting can clear some temporary stored codes, but it does not fix the underlying cause — a genuine fault will simply log again. It does not reset the scheduled service reminder, which is on its own timer.
Can I jump-start it instead of disconnecting?
If the battery is only flat, a jump-start gets you going without disconnecting anything. Disconnecting is for renewing the battery or isolating the car for other work. Either way, if a warning light stays on afterwards, check the code on autodtcs.com.
Independent guide — not affiliated with Volkswagen. Always follow your official service manual and safety precautions. Read our full disclaimer.