Description And Operation; Automatic Day-Night Mirror Description And Operation; Outside Mirror Description And Operation; Outside Mirror - GMC Chevy Colorado 2023 Manual

Description and Operation

Automatic Day-Night Mirror
Description and Operation
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 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 and the Ignition ON/Vehicle in
Service Mode, 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.
Driver Outside Rearview Mirror with
Automatic Day-Night System Operation
(If Equipped)
The automatic day-night feature of the driver outside
rearview mirror is controlled by the inside rearview
mirror. The inside rearview mirror supplies control and
low reference to the driver outside 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 glare from
headlamps behind the vehicle.
Outside Mirror Description and
Operation
Power Mirror System Components
The power mirror system consists of the following
components:
Body Control Module
Driver Seat Adjuster Memory Module
Outside Mirror Switch
Passenger Window Switch
Left Outside Rearview Mirror
Right Outside Rearview Mirror
Power Mirror System Controls
The outside rearview mirror switch is part of the S79D
Driver Front Side Door Window Control Switch and
uses serial data to control the passenger mirror through
the S79P Passenger Front Side Door Window Control
Switch. Each S79 Side Door Window Control Switch
2023 - Colorado Electrical Body Builder Manual
has it own 12V, ground and data communications
circuit along with mirror directional control and mirror
fold circuits.
Driver Mirror Controls
The S79D Driver Front Side Door Window Control
Switch has internal connections for the driver mirror.
When the mirror position switch is active the driver
mirror is commanded to move through bi-directional
motor control circuits. The motor control circuits are
floating while in an inactive state and the switches will
apply power and ground to the control circuits as
necessary to move the mirror in the commanded
direction.
Passenger Mirror Controls
The S79D Driver Front Side Door Window Control
Switch uses serial data circuits to communicate the
active states for the passenger mirror switch to the
S79P Passenger Front Side Door Window Control
Switch. The S79P Passenger Front Side Door Window
Control Switch has internal connections for the
passenger mirror. When the mirror position switch is
active the passenger mirror is commanded to move
through bi-directional motor control circuits. The motor
control circuits are floating while in an inactive state
and the switches will apply power and ground to the
control circuits as necessary to move the mirror in the
commanded direction.
Mirror Position
Mirror position is determined by both horizontal and
vertical position sensors in each of the power mirrors.
Each S79 Front Side Door Window Control Switch
supplies a 5 V reference, low reference, and horizontal
and vertical position signal circuits to these sensors.
The signal circuits are referenced from 5 V by the
S79 Front Side Door Window Control Switch and the
signal circuit voltage levels represent the mirror
positions. The mirror positions are stored in each
S79 Front Side Door Window Control Switch for
memory mirror operation. When the memory seat
module receives a memory recall command, the
memory seat control module will send the go to position
to the S79 Front Side Door Window Control Switch. The
S79 Front Side Door Window Control Switches will then
drive the appropriate mirror motors to the commanded
position sensor settings.
Mirror Select
The S79D Driver Front Side Door Window Control
Switch has internal connections for the mirror select
switch. When the mirror select switch is active the
S79 Front Side Door Window Control Switch will either
control the driver mirror or send a serial data message
to control the passenger mirror.
Folding Mirrors
The S79D Driver Front Side Door Window Control
Switch sends the mirror fold/unfold inputs to the
K9 Body Control Module (BCM) through serial data.
When the BCM receives a fold/unfold signal it will send
a fold/unfold command to the S79 Driver Front Side
Door Window Control Switch which will send a serial
data message to the S79P Passenger Front Side Door
Window Control Switch. The outside mirrors will fold or
Mirrors 2-35