Seat Leon 2012 Owner's Manual page 183

Driving 181
Vehicles with a manual gearbox
The system is completely turned off by moving the control all the way to
B
the right hand side (OFF engaged), or when the vehicle is stationary,
ignition off.
Vehicles with automatic gearbox / DSG automatic gearbox
To completely disengage the system, the selector lever must be placed in
one of the following positions: P, N, R or 1 or with the vehicle stopped and
the ignition turned off.
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