You can stop the lid opening manually by applying pressure. Then you can move it manually to the height you want, then press and hold the closing button until you hear the beep. That sets the opening height as JPP said. My suggestion is to do this with your car 3/4 into your garage so you can more accurately judge he height without fear of damaging your car. With the lid open slowly drive in with someone watching to guide you. If you find it is not opening enough, then, with lid open, simply push it to the correct position and again press and hold the close button to program the new setting.