GM Service Manual Online
For 1990-2009 cars only

Power Lumbar Description w/o A45

The driver and passenger power lumbar systems each consist of a lumbar switch and 2 reversible motors (horizontal and vertical) that operate independently of each other. Each motor contains an electronic circuit breaker (PTC), that will reset only after voltage has been removed from the motor. The lumbar switch, located on the outboard side of each seat, directly controls both lumbar motors located in the seatback.