These instructions apply to the Audi A3 Mk4 (8Y) 2020-Present. For other models, please choose your vehicle here.
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The Audi A3 Mk4 (8Y, 2020–present) has an automatic engine start/stop system that switches the engine off at a standstill to save fuel. If you’d rather keep it running — in traffic, on a hot day, or before working in the engine bay — you switch it off with one button.
How to Turn Off Start/Stop
- Find the AⓇ (A with a circular arrow) button near the gear selector or the dashboard switch bank.
- Press it once — the indicator shows the system is off, and the engine will keep running when you stop.
It Resets Every Drive
Like nearly every car with this feature, the A3 re-enables start/stop each time you switch the ignition off and on. There’s no permanent factory ‘off’ — press the button once per journey if you don’t want it.
Why Switch It Off?
- Before engine-bay work — stops an unexpected restart.
- Stop-go traffic — avoids constant restarts.
- Maximum cabin cooling/heating on extreme days.
On mild-hybrid versions the engine also restarts very smoothly and may “coast” with the engine off while moving — that’s the MHEV system working, not a fault. The system also skips the stop when the battery is low or climate demand is high.
Frequently Asked Questions
How do I turn off auto stop/start on an Audi A3?
Press the AⓇ button near the gear selector; the indicator confirms it’s off.
Can I disable it permanently?
No — it resets to on at every ignition cycle. Press the button each drive.
Why did stop/start come back on?
Switching the ignition off and on re-enables it automatically.
Why won’t the engine stop sometimes even with start/stop on?
A low battery, high climate demand or a gradient will hold the engine running — that’s by design.
If a start/stop fault light shows instead of the normal indicator, look it up on autodtcs.com — a tired 12 V battery is the usual cause. See our A3 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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