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For 1990-2009 cars only

Outside Mirror Description and Operation with RPO DL3

Power Mirror System

Power Mirror System Components

The power mirror system consists of the following components:

    • Driver Door Switch (DDS)--An electronic control module with integrated switches and requires programming when replaced
    • Passenger Door Switch (PDS)--An electronic control module with integrated switches, requires programming when replaced
    • Power Mirror Direction Switch--Integrated into DDS and is a four position momentary switch that provides a signal input to the DDS for up, down, left/extend and right/retract with a mirror switch activation
    • Mirror Select Switch--Integrated into DDS and is a three position switch that allows the operator to select the left or right mirror and also a neutral/fold position
    • Mirror Extend/Retract Switch--Integrated into DDS and is a two position switch that allows the operator to select the mirror extend or mirror retract position
    • Left Outside Power Mirror--Contains both the vertical and horizontal mirror motors
    • Right Outside Power Mirror--Contains both the vertical and horizontal mirror motors
    • Body Control Module--An electronic control module that requires programming when replaced, serves as the power mode master and is the main message handler
    • Horizontal and Vertical Position Sensors, if equipped with memory mirrors--Supplied a 5-volt and low reference by the DDS/PDS and provide a variable voltage signal to the DDS/PDS that is proportional to mirror position
    • Folding Mirror Motor, in each of the outside mirrors, if equipped with power fold mirrors--Provides extend and retract movements of the mirror and is serviced as a complete mirror assembly

Each of the outside power mirrors contains 2 reversible motors to provide horizontal and vertical movement of the mirror glass. The vertical motor operates the up and down directions and the horizontal motor operates the left and right directions. If equipped with power folding mirrors, each outside power mirror will contain a reversible fold motor to operate the extend and retract functions. Each of the mirror motors are circuit breaker protected.

Power Mirror System Controls

The power mirror switch incorporates a 3-position mirror select switch, and a 4-position mirror direction switch. The mirror select switch allows the operator to select the mirror to be moved by selecting the L position for the left power mirror, selecting the R position for the right power mirror or the center which is the neutral position. The mirror direction switch is a 4-position switch that allows the operator to move the selected mirror up, down, left or right.

Power Mirror System Operation

The power mirror switch is integrated into the DDS. The left and right mirror positions of the select switch and 4 positions of the direction switch, when active, will provide a signal to the DDS. If the selector switch is placed in the L position and the up switch is depressed, 2 signals will be supplied to the DDS. The DDS upon receipt of these signals will provide battery voltage to the mirror motor left/up control circuit and ground to the mirror motor down control circuit and the mirror will move up. The remainder of the driver mirror functions operate in the same manner as described above except the DDS will supply battery voltage and ground to the appropriate control circuits for the direction selected. If the passenger mirror is selected and a direction switch is activated, the DDS sends a LAN message to the PDS indicating that the passenger mirror was selected and the direction to be commanded. The PDS will then supply battery voltage and ground to the appropriate control circuits for the direction selected.

Folding Mirror System

Folding Mirror System Controls

The folding mirror switch is integrated into the DDS and incorporates a 2-position mirror extend/retract switch. The mirror extend/retract switch allows the operator to extend or retract the power folding mirrors.

Folding Mirror System Operation

Upon receipt of the required switch input, the DDS will supply battery voltage and ground to the mirror extend/retract motor control circuits to perform the requested extend or retract function. The DDS will also send a LAN message to the PDS indicating the requested function. The PDS will supply battery voltage and ground to the mirror extend/retract motor control circuits to perform the requested extend or retract function.

Heated Outside Rearview Mirror

The DDS and PDS control the activation of the mirror heaters. Upon receiving a serial data message indicating a request for heated mirrors, the DDS and PDS, will apply voltage to the mirror heater element supply voltage circuit. The mirror heaters will remain active until a new message is received indicating rear defogger is to be deactivated.

Outside Mirror Description and Operation without RPO DL3

Power Mirror System Components

The power mirror system consists of the following components:

    • Outside rearview mirror switch
    • Mirror selector switch
    • Left outside rearview mirror
    • Right outside rearview mirror

Each of the outside rearview mirror contains two motors. The vertical motor operates the mirror in the up and down directions, and the horizontal motor operates the mirror in the left and right directions.

Power Mirror System Controls

The outside rearview mirror switch is a four position directional switch: Up, Down, Left and Right.

The mirror select switch is a three position switch: left, center/neutral, and right.

Power Mirror System Operation

The outside rearview mirror switch receives power through the battery positive voltage circuit from the PWR MIR 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 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 positive voltage will be supplied to the left outside rearview mirror vertical motor through the left mirror motor down control circuit and ground through the left mirror motor left control circuit. If the down switch is depressed, battery positive voltage will be supplied to the left outside rearview mirror vertical motor through the left mirror motor left control circuit and ground through the left mirror motor down control circuit.

The remainder of the mirror functions operate in the same manner as described above. Placing the power mirror switch in opposing positions, left/right or up/down, will reverse the polarity to the mirror motor, reversing the direction of movement.

Heated Outside Rearview Mirror Operation

The REAR DEFOG relay controls the operation of the heated outside rearview mirrors. When rear window defogging is requested, the REAR DEFOG relay is energized and B+ is applied to the supply voltage circuit of the mirror heater element, located in the mirror face. A constant ground is also applied to the mirror face. Current will pass through the mirror heater element, warming the mirror, so long as the rear window defogger is commanded ON.