GM Service Manual Online
For 1990-2009 cars only

Without Memory

Ignition positive voltage is supplied to the driver door window/mirror switch when the ignition switch is in the ON position. The ground circuit of the driver door window/mirror switch is grounded by G200.

Each outside rearview mirror has two reversible DC motors. One motor adjusts the mirror to the UP/DOWN (vertical) position and the second motor adjusts the mirror to LEFT/RIGHT (horizontal) position. The driver door window/mirror switch controls mirror direction by changing the polarity of the voltage applied to the motors. The inside rearview mirror can be manually adjusted by tilting the mirror.

With Memory

The outside rearview mirrors contain two reversible DC motors and two position sensors. One motor adjusts the mirror to the UP/DOWN (vertical) position and the second motor adjusts the mirror to LEFT/RIGHT (horizontal) position. The driver memory seat module controls the mirror direction by changing the polarity of the voltage applied to the motors.

The driver memory seat module supplies a 5 volt reference and reference ground to the position sensors. The driver memory seat module monitors the signal circuits of the position sensors to determine the position of the mirrors. The driver memory seat module stores the position of the mirrors when a memory feature is requested.