GM Service Manual Online
For 1990-2009 cars only

Power Lumbar Circuit Description for Chevrolet Blazer - 4WD 2000

Each seat incorporates a lumbar support motor in order to mechanically change the contour of the seat back. Ground is supplied at all times to both lumbar switches. When the lumbar switch is actuated one way or the other, voltage is applied and current flows in the corresponding direction through the lumbar motor.