For 1990-2009 cars

## Power Lumbar Circuit Description Oldsmobile

Battery positive voltage (B+) is supplied at all times to the lumbar seat switch located in the seat from the IP fuse block PWR STS circuit breaker through CKT 1340 (ORN). Push the switch to INFLATE in order to actuate the lumbar air pump. This fills the lumbar bladder. Pushing the switch to DEFLATE allows the bladder to deflate through the lumbar switch. The left lumbar air pump receives ground from G202 through CKT 1250 (BLK). The right lumbar air pump receives ground from G201 through CKT 1450 (BLK).

## Power Lumbar Circuit Description Pontiac w/AL7

The sport seats incorporate a power inflate/power deflate pneumatic system used for controlling the comfort features of the seats by inflating or deflating air cells within the seats. The pneumatic system consists of the following components:

• | Console seat switch

• | Seat air pump

• | Seat air control module

• | Seat cushion air valves

Battery positive voltage (B+) is supplied at all times to the console seat switch via CKT 640 (ORN). Set the seat select switch to the LEFT or RIGHT position whenever an adjustment is to be made. This action supplies battery positive voltage (B+) to each of the four comfort switches and prepares a ground path for either the LH seat cushion air valve or RH seat cushion air valve.

All four of the comfort feature switches operate in a similar manner. If any one of them is moved to the INFLATE position, battery positive voltage (B+) is supplied via CKT 766 (WHT) to the inflate relay. The inflate relay is then energized. When any one of the switches is moved to the DEFLATE position, battery positive voltage (B+) is supplied via CKT 764 (GRY) in order to energize the deflate relay. The inflate and deflate relays are grounded via CKT 1250 (BLK) to ground G202.

Simultaneously, battery positive voltage (B+) is also supplied to the associated solenoid coil in the seat cushion air valve from the other half of the feature switch. If the seat select switch is moved to the LEFT position and the middle lumbar switch is held in the INFLATE position, the inflate relay is energized via CKT 766 (WHT) and the middle lumbar solenoid in the LH seat cushion air valve is energized via CKT 763 (BRN). Battery positive voltage (B+) is also applied to the middle lumbar solenoid in the RH seat cushion air valve. However, the solenoid is not energized because there is not a path to ground. The ground path for the LH seat cushion air valve is via CKT 797 (TAN) from the console seat switch, through the seat select switch, via CKT 769 (BLK/WHT) from the seat air control module, through the normally closed contacts of the pressure cut-out relay, and to ground G202 via CKT 1250 (BLK) through the seat air control module.

The purpose of the deflate and inflate relays is to supply battery positive voltage (B+) of the proper polarity to the seat air pump. When the inflate relay is energized, battery positive voltage (B+) is supplied through the closed contacts of the inflate relay to the seat air pump via CKT 768 (TAN). The seat air pump is grounded through the normally closed contacts of the deflate relay via CKT 767 (PPL) through the seat air control module.

When the deflate relay is energized, battery positive voltage (B+) is supplied to the seat air pump through the closed contacts of the deflate relay via CKT 767 (PPL). The seat air pump assembly is grounded through the normally closed contacts of the inflate relay via CKT 768 (TAN) through the seat air control module.

In this way the seat air pump runs in either direction in order to inflate or deflate the bladders in the seat as required.

If any of the bladders become fully inflated or deflated, the increased pressure or vacuum operates the pressure cut-out switch. This allows the pressure cut-out relay to be energized whenever the air pump is operated. When the pressure cut-out relay is energized, the air pump motor circuit and solenoid valve circuit are interrupted.