David,

Do not have the steps in front of me, retired. If I remember correctly, hold the horn button in the on position. Turn key on, release horn then quickly turn it on and release again. Display should show handle calibration. Move handle completely forward and reverse within 10 seconds. Make sure when moving handle it is smooth and stop at each end for 2 seconds. If the display does not show handle calibration, press the brake pedal one time and check screen again. Be careful as you can access the wrong menu and change lift parameters. This could stop the operation of the lift. Good Luck