Contents Wiring diagrams Section: Mirrors All sections

Mirror System: Overview Cadillac STS I facelift

Mirrors ~1279 words

Circuit/System Description

The outside mirror control switch is contained within the driver door switch assembly (DDSA). The DDSA sends this message via the serial data circuit to the driver door module (DDM) to move the left mirror or the passenger front door module (PDM) to move the right mirror. The DDM or PDM then applies voltage and ground to the appropriate circuits of the appropriate mirror motor to move the mirror vertically and/or horizontally.

The driver door module (DDM) and passenger door module (PDM) receive mirror position signals from the mirror horizontal and vertical position sensors. These signals are used by the door modules for memory recall functions of the driver and passenger mirrors. The door modules command the mirror memory settings based upon the voltage level received back from the position sensors. Each door module provides a 5 volt supply, a signal, and ground circuit for each of the position sensors. The horizontal and vertical position sensors are variable resistors that the door modules monitor voltage levels across. When a memory setting is recalled, the door modules command the mirror motors in the appropriate directions until the stored position sensor voltage levels are achieved. The DDM and PDM monitor the signal circuits to determine if the voltage level is out of range.

The DDSA has an additional power folding mirror switch built into it and each mirror contains an additional power folding mirror motor. When the switch is activated to fold mirrors, the switch contacts close, the DDSA interprets the signal input, and sends the command on to the DDM and PDM. The DDM and PDM each apply battery voltage and ground to the appropriate circuits of their respective power folding motor in order to retract the mirrors. When the switch is activated to unfold the mirrors, the door modules reverse the polarity of the voltage and ground applied to the reversible folding motors to move both mirrors to the fully extended position.

The heated mirrors are connected to the DDM and PDM. The DDM and the PDM receive a serial data message from the HVAC control module indicating that the rear window defogger switch has been activated. If conditions are correct, the DDM and PDM will apply battery voltage to the outside rearview mirror heating element control circuits.

The inside rearview mirror uses 2 photocell sensors. One sensor is the rear light sensor, located on the face side of the mirror, facing the rear of the vehicle. The rear light sensor is used to determine light conditions present at the mirror face. The other sensor is the front light sensor, located on the backside of the mirror, facing the front of the vehicle. The front light sensor is used to determine the exterior light conditions at the front of the vehicle. With a low exterior light condition detected by the front light sensor and a high light condition from the rear light sensor, the inside rearview mirror will automatically darken the face of the inside rearview mirror and the left outside rearview mirror. The inside rearview mirror provides a signal circuit and a low reference circuit to the left mirror face to darken the mirror when needed.

With the gear selector lever in the REVERSE position, backup lamp supply voltage is supplied as an input to the inside rearview mirror. The mirror monitors this input to disable the automatic day-night feature. This allows the driver to see objects in the mirror clearly when backing up, regardless of the rear light sensor status.

The inside rearview mirror uses 2 photocell sensors. One sensor is the rear light sensor, located on the face side of the mirror, facing the rear of the vehicle. The rear light sensor is used to determine light conditions present at the mirror face. The other sensor is the front light sensor, located on the backside of the mirror, facing the front of the vehicle. The front light sensor is used to determine the exterior light conditions at the front of the vehicle. With a low exterior light condition detected by the front light sensor and a high light condition from the rear light sensor, the inside rearview mirror will automatically darken the face of the inside rearview mirror.

With the gear selector lever in the REVERSE position, backup lamp control voltage is supplied as an input to the inside rearview mirror. The mirror monitors this input to disable the automatic day-night feature. This allows the driver to see objects in the mirror clearly when backing up, regardless of the rear light sensor status.

This feature allows the operator to simultaneously retract both mirrors to a fully folded position. The driver door switch assembly (DDSA) contains the power folding mirrors switch and, each mirror contains an additional power folding mirror motor. The DDSA sends a message to the DDM and PDM when the power folding mirror switch is activated to the retract or extend positions. When the door modules detect an active power folding mirror command from the DDSA, the DDM and PDM each apply battery voltage and ground to the appropriate circuits of their respective power folding motor in order to retract the mirrors. When the switch is activated to unfold the mirrors, the door modules reverse the polarity of the voltage and ground applied to the reversible folding motors to move both mirrors to the fully extended position.

The driver door module (DDM) and passenger door module (PDM) each provide motor control output functions for their respective mirrors. These output controls allow each door module to command their respective power mirrors in horizontal and vertical positions. The driver door switch assembly (DDSA) sends a serial data message to the door modules when the mirror switch is activated to the up, down, left or right positions. When the door modules detect an active mirror command from the DDSA, they will command the respective mirror motor in the appropriate direction. Each door module commands their respective mirror motors by applying a ground or voltage to the control circuit, depending on the desired mirror position.

The driver door module (DDM) and passenger door module (PDM) each provide motor control output functions for their respective mirrors. These output controls allow each door module to command their respective power mirrors in horizontal and vertical positions. When the door modules detect an active mirror command they will command the respective mirror motor in the appropriate direction. Each door module controls their respective mirror motors by applying a ground or voltage to the control circuit, depending on the desired mirror position.

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 face 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 rear of the mirror or windshield side. The ambient light sensor is used to determine the exterior light conditions. With a low exterior light condition detected, and a high light condition from behind of the car, 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 exterior 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. The mirror monitors this input to disable the automatic day-night feature. This allows the driver to see objects in the mirror clearly when backing up, even during the night.