Lumbar Switch
WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.
The lumbar switch provides both power and ground to the lumbar motor. Battery positive voltage is supplied at all times to the lumbar adjuster switch from the MSM/RT FRT PWR SEAT Circuit Breaker located in the rear fuse block. Ground for the lumbar adjuster switch is supplied from the G300 ground stake.