Circuit Description

The lumbar support system is a power inflate/power deflate pneumatic system used for controlling comfort seat features by inflating or deflating the air cells within the seat. The following are the major components of the pneumatic system:
^ The seat/lock switches
^ The lumbar seat module

Battery positive voltage (B+) is applied at all times through the right rear fuse block PWR STS circuit breaker via CKT 1340 (ORN) to the lumbar seat module. Battery positive voltage (B+) is applied at all times to the seat/lock switches through the right rear fuse block IP 1 fuse via CKT 40 (ORN). Placing a switch in the INFLATE position actuates the seat air pump which fills the lumbar bladder. Placing the switch in the DEFLATE position allows the bladder to deflate. There are 2 separate areas, UPPER and LOWER, within each seat that inflate or deflate. When a lumbar switch is operated, a solenoid valve opens, allowing air into or out of the respective lumbar bladder.