Manual gearshifting: kickdown is only possible if you have activated manual gearshifting with the steering wheel gearshift paddles. If you have activated manual gearshifting with the button in the centre console, kickdown is not possible.
During kickdown, you cannot shift gears using the steering wheel gearshift paddles. The automatic transmission shifts up to the next gear when the maximum engine speed is reached to protect the engine from overrevving.