System for automatic switching on or adjusting of an adjustment device for adjusting a horizontal and/or vertical position of a view window of a head-up-display apparatus of a vehicle, comprising - a head-up-display apparatus which is designed to be able to project a display on a projection surface of a vehicle, and - an adjustment device coupled with the head-up-display apparatus with an operating apparatus which is adapted to be able to adjust the horizontal and/or vertical position of the view window of the head-up-display apparatus by means of an operating action at the operating apparatus, wherein the adjustment device with the operating device is further adjusted for adjusting at least one external mirror and/or an interior mirror of the vehicle characterised in that the system further - has a detecting apparatus for detecting and evaluating a viewing direction of a user of the head-up-display apparatus and - has a control apparatus coupled with the adjustment device and the detecting apparatus, wherein - the control device is designed, - to switch on/adjust the adjustment device for adjusting the horizontal and/or vertical view window of the head-up-display apparatus of the vehicle, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the projection surface, and - - to switch on/adjust the adjustment device for adjusting an external mirror by means of an operating action of the user at the operating apparatus, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the external mirror, and/or - - to switch on/adjust the adjustment device for adjusting an interior mirror by means of an operating action of the user of the operating apparatus, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the interior mirror. - a head-up-display apparatus which is designed to be able to project a display on a projection surface of a vehicle, and - an adjustment device coupled with the head-up-display apparatus with an operating apparatus which is adapted to be able to adjust the horizontal and/or vertical position of the view window of the head-up-display apparatus by means of an operating action at the operating apparatus, wherein the adjustment device with the operating device is further adjusted for adjusting at least one external mirror and/or an interior mirror of the vehicle - has a detecting apparatus for detecting and evaluating a viewing direction of a user of the head-up-display apparatus and - has a control apparatus coupled with the adjustment device and the detecting apparatus, wherein - the control device is designed, - to switch on/adjust the adjustment device for adjusting the horizontal and/or vertical view window of the head-up-display apparatus of the vehicle, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the projection surface, and - - to switch on/adjust the adjustment device for adjusting an external mirror by means of an operating action of the user at the operating apparatus, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the external mirror, and/or - - to switch on/adjust the adjustment device for adjusting an interior mirror by means of an operating action of the user of the operating apparatus, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the interior mirror. - - to switch on/adjust the adjustment device for adjusting an external mirror by means of an operating action of the user at the operating apparatus, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the external mirror, and/or - - to switch on/adjust the adjustment device for adjusting an interior mirror by means of an operating action of the user of the operating apparatus, inasmuch as and as long as it is recognised by the detecting apparatus that the user is looking in the direction of the interior mirror.