Power Seat and Lumbar Switches
WARNING: This page is about a different car, the 2011 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.
Battery positive voltage is supplied at all times to the driver seat adjuster switch and the lumbar adjuster switch from the MSM and a 10 A fuse located in the rear fuse block. When the seat or lumbar switches are pressed they send a 12 V signal to the MSM. The MSM commands the selected seat or lumbar motor to move in response to the switch inputs.