Circuit/System Description
The heated outside rearview mirrors operate when the rear window defogger is turned ON and will turn OFF when the rear window defogger is turned OFF.
The automatic day-night rearview mirror uses 2 photocell sensors that detects an increase in light. One sensor is located in the rear side of the mirror. This sensor determines the light condition present at the mirror face. The other sensor is the ambient light sensor, located on the front of the mirror or windshield side. This sensor determines the amount of light present at the mirror. When the ambient light sensor senses a low light condition and a high light condition from behind at the headlight sensor, the inside rearview mirror will automatically darken the face of the mirror.
The outside rearview mirror switch supplies the voltage and the ground for the rearview mirror motors. Depending on what circuits are supplied the voltage and ground will determine the direction the mirror will move.
Power Mirror System Operation
The outside rearview mirror switch receives power through the battery positive voltage circuit from the PWR MIRROR 2-amp fuse. The power mirror switch also receives a constant ground.
The 4 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.
Inside Rearview Mirror with the Automatic Day-Night Feature System Operation
The inside rearview mirror uses 2 photocell sensors. One sensor is the headlight sensor, located on the rear side of the mirror. The headlight sensor is used to determine light conditions present at the mirror face. The other sensor is the ambient light sensor, located on the front of the mirror or windshield side. The ambient light sensor is used to determine light conditions present at the mirror. With automatic day-night feature enabled, the mirror uses ambient light sensor to determine the exterior light condition. With a low light condition detected, and a high light condition from behind at the headlight sensor, the inside rearview mirror will automatically darken the face of the mirror.
In the daytime, the mirror is in a normal state because of the high light condition that is indicated by the ambient light sensor. With the gear selector lever in the REVERSE position, backup lamp supply voltage is supplied as an input to the inside rearview mirror. In night time conditions only, the mirror monitors this input to disable the automatic day-night feature which allows the face to gradually change to a normal state. This allows the driver to see objects in the mirror clearly when backing up.