Circuit/System Description

WARNING: This page is about a different car, the 2022 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.

The S65 Front Seat Lumbar Switch provides both power and ground to the M53 Front Seat Back Lumbar Motor. When the lumbar switch is in an inactive state, the switch contacts are closed to the switch ground circuit.

The M53 Front Seat Back Lumbar Motor is reversible. For example, when the lumbar forward switch is pressed to move the lumbar support forward, battery voltage is applied through the switch contacts and the lumbar motor forward control circuit to the motor. With the lumbar motor rearward control circuit grounded through the closed switch contacts to the lumbar switch ground circuit, the motor runs in order to drive the lumbar support forward toward the occupants back until the switch is released. Moving the lumbar support rearward works similarly to moving the lumbar support forward, except that battery positive voltage and ground are applied on opposite circuits causing the motor to run in the opposite direction.