These instructions apply to the Audi A4 Mk5 (B9/8W) 2015-Present. For other models, please choose your vehicle here.
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Your Audi A4 (B9/8W, 2015–present) switches the engine off at a standstill to save fuel. When you’d rather it stayed running — heavy traffic, a hot day, or before any under-bonnet work — one button switches it off.
Turning Start/Stop Off
- Find the AⓇ button (an “A” circled by an arrow), usually near the gear selector or the dashboard switches.
- Press it once; the indicator confirms the system is off and the engine stays running at stops.
Why It’s On Again Next Time
The A4 switches start/stop back on at every ignition cycle — there’s no permanent off from the factory. Tap the button once at the start of each drive if you don’t want it.
Reasons to Switch It Off
- Engine-bay jobs — no surprise restart.
- Heavy traffic — no constant cycling.
- Hot or cold extremes — steadier climate output.
The system also declines to stop on its own when the battery is low, the cabin still needs heating/cooling, or you’re on a slope — all normal. Mild-hybrid A4 versions also coast with the engine off while moving as part of normal operation.
Frequently Asked Questions
How do I switch off auto stop/start on an Audi A4?
Press the AⓇ button near the gear selector; the indicator shows it’s off.
Can it stay off for good?
No — it re-arms each ignition cycle. Press the button per drive.
Why did it switch itself back on?
Cycling the ignition re-enables it automatically.
Why won’t the engine cut sometimes?
Low battery, high climate load or a gradient keeps it running by design.
If a start/stop fault symbol shows rather than the normal one, look it up on autodtcs.com — usually a weak 12 V battery. See our A4 battery guide.
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.
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