Longitudinal seat adjustment device, method for adjusting a seat, and motor vehicle with the same longitudinal seat adjustment device

The present invention relates to a longitudinal seat adjustment device (1), comprising a rail (10) running along a longitudinal axis (X), a slide (20) with an electric drive device (40), by means of which the slide can be moved along the longitudinal axis (X) of the rail (10), and a first control unit (15) and a second control unit (25), wherein the first control unit (15) is fixedly connected to the rail (10) and the second control unit (25) is arranged on the slide (20), wherein the first control unit (15) and the second control unit (25) are connected via an electrical conductor (50) which can be energized by a voltage source (4) with a supply voltage (S1), wherein the second control unit (25) can control the drive device (40), and wherein the first control unit (15) and the second control unit (25) communicate via a communication signal (S2) that can be modulated to the supply voltage.