GM Service Manual Online
For 1990-2009 cars only

Power is supplied to the driver seat adjuster switch from the power seat circuit breaker D through CKT 340.

Three reversible motors operate the power seat. Separate motors raise the front and rear height of the seat. The front and the rear height can be raised or lowered independently of each other. When the entire seat adjuster switch is pushed to the UP or DOWN position, both motors operate to move the front and rear of the seat at the same time.

The entire seat adjuster switch operates the forward/back adjuster motor. Battery voltage is applied through the switch contacts and CKT 285 to the forward/back adjuster motor when the switch is held in the FORWARD position. The motor is grounded through CKT 284. The seat adjuster switch is grounded through CKT 150 to G302.

CKT 284 receives battery voltage and CKT 285 is grounded when the switch is held in the BACK position. The reversed polarity causes the motor to run in the opposite direction and drive the seat backward.

The front or rear height adjuster motors work in a similar way when the FRONT HEIGHT or REAR HEIGHT switch is operated.

The entire seat is raised if the entire seat adjuster switch is held in the UP position. This applies battery voltage through the CKT 282 and CKT 286 to the rear height and front height adjuster motor. The motors are grounded through CKT 283 and CKT 287. The seat adjuster switch is grounded through CKT 150 to G302. Both motors operate to drive the entire seat to up or down.

Each motor contains a solid state self-resetting circuit breaker in order to protect it from overload. The electronic circuit breaker (ECB) increases if a motor is overloaded and returns to normal if after the voltage is removed from the motor terminals.