GM Service Manual Online
For 1990-2009 cars only

Outside Mirror Description and Operation Power Mirrors

Power Mirror System Components

The power mirror system consists of the following components:

    • Power mirror switch
    • Selector switch
    • Left outside power mirror
    • Right outside power mirror
    • MIR/LOCK 3A fuse

Each of the outside power mirrors contains two reversible motors. The vertical motor operates the up and down directions and the horizontal motor operates the left and right directions. Each of the power mirror motors are circuit breaker protected.

Power Mirror System Controls

The power mirror switch incorporates a mirror select switch and a four position mirror direction switch.

The mirror select switch allows the operator to select the mirror to be moved by rotating counterclockwise to the L position (left outside power mirror) or rotating clockwise to the R position (right outside power mirror).

The mirror direction switch is a four position switch that allows the operator to move the selected mirror up, down, left or right.

Power Mirror System Operation

The power mirror switch receives power through the battery supply voltage circuit and the MIR/LOCK fuse. The power mirror switch also receives a constant ground.

The four positions of the direction switch have dual switch contacts. Each of the contacts are connected to opposing sides of the appropriate power mirror motors through the selector switch. The selector switch interrupts or completes these circuits depending on the position of the selector switch (L or R).

If the selector switch is placed in the L position and the up switch is depressed, battery voltage will be supplied to the left outside power mirror vertical motor through the left mirror motor up direction circuit and return to the power mirror switch through the mirror motor common circuit then to ground and the mirror will move up. If the down switch is depressed, the common circuit supplies battery voltage and the left mirror motor up direction circuit completes the path to the power mirror switch then to ground and the mirror will move down.

The remainder of the mirror functions operate in the same manner as described above. The thing to remember is, that by placing the power mirror switch in opposing positions (left/right or up/down) will reverse the polarity of the mirror motor, utilizing the same circuits and the power mirror will move accordingly.

Outside Mirror Description and Operation Folding Mirrors

Power Folding Mirrors System Components

The power folding mirrors system consists of the following components:

    • Outside rearview folding mirror switch
    • Left folding mirror
    • Right folding mirror
    • RDO IGN 10A fuse

Power Folding Mirrors System Controls

The power folding mirrors will operate anytime the ignition is in the ACCY or ON position and anytime RAP is active. The outside rearview folding mirror switch controls both mirrors simultaneously and has three positions:

    • Neutral -- no mirror movement
    • Extend -- mirrors move outward
    • Retract -- mirrors move inward

The mirror motors are thermally protected against an overload condition.

Power Folding Mirrors Operation

Voltage is supplied to the outside rear view folding mirror switch through the RDO IGN fuse and the RAP fuse supply voltage circuit. The outside rear view folding mirror switch also receives a constant ground.

When the EXTEND button is pressed, voltage is supplied to the mirror motor through the folding mirror extend circuit. The other side of the motor is connected to outside rearview folding mirror switch to ground through the folding mirror retract circuit. The motor then runs to extend the mirror.

When the RETRACT button is pressed, voltage is supplied to the mirror motor through the folding mirror retract circuit. The other side of the motor is connected to outside rearview folding mirror switch to ground through the folding mirror extend circuit. The motor then runs to retract the mirror.

Outside Mirror Description and Operation Heated Mirrors

Heated Mirror System Components

The heated mirror system consists of the following components:

    • RR Defog relay
    • Electronic Climate Control (EEC) module
    • Left outside power mirror
    • Right outside power mirror
    • HTD MIRROR 10A fuse

Heated Mirror System Controls

The heated mirror system is activated by depressing the rear window defogger switch, which is part of the EEC module. For further information on the rear window defogger operation, refer to Rear Window Defogger Description and Operation .

Heated Mirror System Operation

The heated mirror system operates in parallel to the rear window defogger. Each outside rearview mirror contains a heating element that is connected to a constant ground source. When the rear window defogger system is active, battery voltage is available at the HTD MIRROR fuse and to the outside rearview mirrors through the heated mirror supply voltage circuit. The mirrors will heat up to remove ice, snow or frost and will automatically deactivate when the rear defogger system has timed out, approximately 10 minutes.

Outside Mirror Description and Operation Auto - Day Night Mirrors

Mirrors -- Outside Automatic Day/Night Feature

The automatic day/night feature of the driver outside rearview mirror is controlled by the inside rearview mirror. The inside rearview mirror supplies a signal and a low reference to the driver outside rearview mirror. The voltage on the signal circuit of the driver outside rearview mirror varies between 0.5 to 1.5 volts depending on light conditions present at the inside rearview mirror. At night, with the automatic day-night feature enabled, the driver outside rearview mirror will automatically darken with the inside rearview mirror to reduce the glare from the headlamps from behind. The voltage on the signal circuit of the driver outside rearview mirror will be near 1.5 volts. In the daytime, the mirrors are in a normal state. The voltage on the signal circuit of the driver outside rearview mirror may be less than or near 0.5 volts. Refer to Automatic Day-Night Mirror Description and Operation in Stationary Windows for further description and operation of the inside rearview mirror.