Mirrors: Description and Operation
Rear View Mirrors
COMPONENT LOCATION
NOTE: RHD (right-hand drive) shown, LHD (left-hand drive) similar
OVERVIEW
Rear view mirrors consist of an interior mirror on the windshield, an exterior mirror on each front door cheater and, for the Japan market, a driver proximity mirror on the front left corner of the hood.
INTERIOR MIRROR
Manual Dimming Interior Mirror
Automatic Dimming Interior Mirror (All Except Japan)
Automatic Dimming Interior Mirror (Japan Only)
The interior mirror is installed on a stud bonded to the windshield. Trim finishers cover the mounting stem of the interior mirror and, where fitted, the rain/light sensor. The interior mirror incorporates either manual or automatic dimming, depending on market and trim level. Some vehicles may also incorporate a HomeLink� universal transmitter. Manual dimming is performed by rotating a knob on the underside of the mirror. Automatic dimming is performed by electrochromic mirror glass.
NOTE: HomeLink is a registered trademark owned by Johnson Controls Inc.
On Japan market vehicles, the interior mirror also incorporates the electronics for the infrared receiver of the central locking system. The infrared receiving diodes are installed in a housing on the underside of the mirror (the housing is the dimming knob on manual mirrors). Operation of the infrared receiver is controlled by the GEM (generic electronic module).
Interior mirrors with automatic dimming are connected to the vehicle wiring by an electrical connector in the mounting stem. The electrochromic mirror circuits and, where fitted, the universal transmitter, are powered by a feed from the CJB (central junction box) when the ignition switch is in position II. On Japan market vehicles, the interior mirror also receives a permanent power feed from the CJB (central junction box) for the infrared receiver circuits.
Universal Transmitter
WARNING: The universal transmitter must not be used with any garage door that lacks safety 'stop' and 'reverse' features, as required by federal safety standards (this includes any garage or door opener model manufactured before April 1 1982). A garage door opener which cannot 'detect' an object in the path of a closing door and then automatically 'stop' and 'reverse' the door, does not meet current federal safety standards. Using a garage door opener without these features increases the risk of serious injury or death.
The universal transmitter can operate up to 3 home or office remotely operated systems (e.g. garage door/gate openers, lighting and security systems), replacing the individual hand held transmitters required for each system. The universal transmitter can learn the radio frequency codes of most current transmitters.
The universal transmitter incorporates 3 buttons, one for each channel, and an amber LED (light emitting diode) installed on the underside of the interior mirror. When one of the buttons is pressed the universal transmitter outputs the radio signal programmed for the related channel (if any) and illuminates the LED (light emitting diode) to confirm transmission.
EXTERIOR MIRRORS
The exterior mirrors are bolted to the front door structure and incorporate the following features:
^ Convex mirror glass.
^ Electric adjustment.
^ Mirror heating.
^ Automatic dimming (model and market dependant).
^ Memory recall and reverse dipping (model and market dependant).
^ Mirror fold back function (model and market dependant).
^ Approach lighting (model dependant).
Operation of the exterior mirrors is controlled by the 2 front door modules and the GEM (generic electronic module). The door modules and the GEM (generic electronic module) communicate with each other on a P bus. The switches for adjustment and folding of the exterior mirrors are incorporated into the DDM (driver door module). The door modules interpret the P bus signals and control switch inputs into appropriate outputs for the exterior mirrors. For operation of the various exterior mirror functions the 2 door modules are powered by a permanent battery feed from the CJB (central junction box).
Heating
Heating of the exterior mirrors is controlled by the GEM (generic electronic module) and the respective door modules, and is active while the ignition switch is in position II.
The GEM (generic electronic module) receives the ambient air temperature value from the instrument cluster via the K bus. The GEM (generic electronic module) converts the ambient air temperature value to an on-time percentage and transmits it on the P bus to the two door modules, which then energize the exterior mirror heating elements accordingly. The on-time percentage is increased while the windshield wipers are on.
On vehicles with the parked heating function, exterior mirror heating may also operate when the parked heating function is active, depending on the ambient air temperature.
Dimming
Exterior mirrors with automatic dimming are slaved to the interior mirror. The interior mirror determines the amount of dimming required and energizes the electrochromic elements in the exterior mirrors accordingly. Feed and ground wires from the interior mirror, for the electrochromic elements in the exterior mirrors, bypass the door modules and connect directly to the exterior mirrors.
Mirror Memory
The seat, exterior mirrors and steering column memory functions are integrated into the GEM (generic electronic module).
The driver and front passenger door modules control the mirror memory while the driver seat memory switch pack controls the seat and steering column memory.
Located on the outboard side of the driver seat plinth, the memory switch and memory pre-set buttons can be used to store 3 different mirror positions. When a position is stored or recalled, the information is transmitted to the GEM (generic electronic module) via the K bus. It is then relayed to the door modules via the P bus. Each door module evaluates the recalling and storage commands transmitted via the P bus for positions 1 to 3 and performs the necessary adjustments.
If a manual adjustment is selected while the mirror memory is operating, it will over-ride the memory recall function.
For mirror memory to operate, the mirror adjustment potentiometers must deliver a voltage value in the range of 80mV - 4.8V. Should a voltage applied be outside of this range the mirror will not operate when memory is selected.
Reverse Dipping
If reverse gear is selected when the ignition is at position I or II, the passenger exterior mirror dips to provide a better view of the kerb. The mirror returns to it's original position immediately reverse gear is disengaged.
The kerb view mirror position can be adjusted using the mirror adjustment multi-directional switch while reverse gear is selected and the ignition switch is in position I or II.
DRIVER PROXIMITY MIRROR (JAPAN ONLY)
The driver proximity mirror allows the driver to see into the 'blind spots' below the level of the hood during low speed maneuvering. The mirror is manufactured in black plastic and consists of a lense housing mounted on a pivot arm, which is attached to the hood. Two lenses in the housing provide coverage across the front and along the LH (left-hand) side of the vehicle. The mirror can be manually adjusted in the horizontal plane only.
CONTROL DIAGRAM
NOTE: A = Hardwired; B = K bus; M = P bus
NOTE: The hardwired connection between the interior mirror (item number 11) and the GEM (generic electronic module) (item number 9) is only present on Japanese specification vehicles.
PRINCIPLES OF OPERATION
Electrochromic Mirror
The electrochromic mirrors automatically dim to reduce glare from the headlights of following vehicles in dark or low light conditions. In addition to dimming the interior mirror, the electrochromic mirror circuits also control the dimming of the two exterior mirrors, via power feed and ground connections with the 2 exterior mirrors.
A light sensor on the front of the interior mirror monitors ambient light at the front of the vehicle and a light sensor in the interior mirror glass monitors the light coming from behind the vehicle. When the light from behind the vehicle exceeds the ambient light level, the electrochromic circuits simultaneously dim the interior and exterior mirrors. Dimming is inhibited when reverse gear is selected. The interior mirror is provided with a reverse gear signal by the LCM (lighting control module).