GM Service Manual Online
For 1990-2009 cars only

There are three reversible motors that operate the power seats. One motor raises or lowers the front of the seat. One motor raises or lowers the rear of the seat. The third motor moves the seat forward or backward. Power is supplied from the SEAT CB fuse (located in the fuse block) to the left and the right power seat switches via CKT 1440 (ORN). Ground path is provided via CKT 2350 (BLK) to ground G304.

The direction the motor operates depends on the polarity of the supply voltage. When the up/down or the forward/rearward switches are operated, the power and ground paths are reversed respectfully causing the motor to run in both directions. You can service the forward/rearward and the recliner motors individually. Service the front and rear tilt motors as one assembly.