Power Seat and Lumbar Switches
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. 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 seat adjuster switch and the lumbar switch from the MSM and a 10 A fuse located in the I/P fuse block. When the seat or lumbar switches are pressed they send a 12 V signal to the MSM. The MSM then commands the selected seat motor to move in response to the switch input.