The headlamp units are primarily made of plastic and make use of free-form reflectors in order to optimize light distribution.
The transparent plastic cover is made from polycarbonate, which is coated for protection against scratches and cracks.
In the event of damage to the cover the entire headlamp unit needs to be replaced.
The turn signal lamps and side lights are also integrated in the headlamp unit.
The manual headlamp leveling system operates with an electric motor which is controlled via a rotary control in the instrument cluster.
For conventional headlamps, adapting the vehicle to conform to country-specific traffic situations (left/right-hand side traffic) during travel is accomplished by affixing punched adhesive strips to specific areas of the headlamp.
All conventional headlamps use 12 V bulbs with a spiral-wound filament.
WARNING:High voltages of up to 30 kV are present in the system. Ensure that the headlamp assembly electrical connector is disconnected if the headlamp assembly is removed.
High intensity discharge headlamps are optionally available.
A single xenon high intensity discharge bulb in the outer projector is used both for low and high beams.
If the battery voltage drops below 7 volts during engine start-up, the high intensity discharge headlamps are switched off by the GEM. On vehicles built from 03/2007, the headlamps are switched on again 50ms after being switched off by the GEM.
In order to prevent dazzling the oncoming traffic in low beam mode, the light cone is modified by means of a shutter. An additional reflector is provided for the high beam, which is generated using a conventional bulb with a spiral-wound filament. This bulb is switched on when the headlamps are switched to high beam and when the headlamp flasher is operated.
The turn signal lamps and side lights are the same as in conventional headlamps.
An automatic headlamp leveling system is a legal requirement for vehicles with high intensity discharge headlamps.
The automatic headlamp leveling system is a second-generation dynamic system which provides additional benefits for the driver in terms of improved illumination of the road due to improved control over the headlamp beam.
In a static system, the vehicle is only considered as a stationary object, whereas a dynamic system also takes into account the dynamic changes to the inclination of the vehicle owing to load changes whilst driving.
The system is designed to respond to changes in the inclination of the vehicle caused by the long-term effects of aerodynamic forces acting on the vehicle (e.g. due to continuous driving at high speeds).
In order to prevent unnecessary changes in the height of the headlamp beam, the system filters out surface irregularities and any pitching of the vehicle under braking and acceleration.
Accordingly, the system needs to be set up with WDS after any components are replaced or any other repairs are carried out.
The front and rear sensors are Hall sensors, which transmit an analog signal to the control module.
Autolamps
CAUTION:On vehicles with autolamps, retrofitting with daytime running lamps is not permissible, as otherwise, the engine cannot be stopped when the lighting is switched on.
CAUTION:On vehicles with autolamps, the daytime running lamp fuse must not be fitted, as otherwise, the engine cannot be stopped when the lighting is switched on.
The combined rain sensor/light sensor is attached to the windshield, near to the interior rear view mirror.
The ambient light sensor determines the general light intensity. For this purpose, it records the light over as wide an angle as possible, without taking the direction of incidence into account.
The front light sensor determines the light intensity directly in front of the vehicle.
If both the ambient light sensor and the front light sensor detect a sudden reduction in light intensity at the same time, then an algorithm-based calculation is used to determine the fact that the vehicle has entered a tunnel, a multi-storey car park or a long underpass.
In this type of case a request to switch on the exterior lights and the display lamps in the instrument cluster is transmitted to the GEM.
If the vehicle is suddenly thrown into the shade by a large truck, the two sensors will register different light intensities. In this case, the algorithm-based calculation will not result in the lights being switched on.
In vehicles built from 07/2004, a stepped switch-off of the low beams, side lamps, license plate lamps as well as the instrument cluster and instrument panel illumination is implemented in the GEM. If the ambient light changes from dark to bright, the GEM first switches off the low beams. The side lamps, license plate lamps, as well as the instrument cluster and instrument panel illumination are switched off approx. 6 seconds after the low beams have been switched off.
Adaptive front lighting
1
-
Adaptive front lighting actuator motor
2
-
Headlamp leveling motor
Vehicles with conventional lighting (low beam with projector) can optionally be equipped with the newly developed adaptive front lighting. The system is not compatible with automatic headlamp inclination and only works when the lights are switched on.
The adaptive front lighting module must be configured for the various vehicle versions (wagon, 3-door, 5-door, engine type, RHD/LHD etc.) using the Worldwide Diagnostic System (WDS).
During cornering, the dipped light projectors swivel toward the inside of the curve, with a maximum correction angle of 9° for the projector on the outside of the curve and 14° for the projector on the inside of the curve.
When reverse gear is engaged, adaptive front lighting is disabled. When reverse gear is disengaged again and the vehicle moves at a speed above 3 km/h, the adaptive front lighting follows the relevant steering movements.
When performing parking maneuvers at a speed below 3 km/h, the adaptive front lighting swivels, in accordance with the country-specific configuration (LHD/RHD), to the relevant edge of the road in order to avoid dazzling the oncoming traffic when the steering wheel is turned in the opposite direction.
The straight ahead position of the steering should be checked using WDS prior to headlamp adjustment. For this purpose, the headlamp leveling system must be in the "0" position and the steering wheel in the "0" (+/- 3°) position.
The adaptive front lighting actuator motors are stepper motors.
The headlamp leveling system motors are DC motors.
If there is a system fault with the adaptive front lighting actuator motors, the fault code "Advance Front Light Failure (adaptive front lighting malfunction)" will be shown in the driver information display of the instrument cluster and the indicator will flash.
In the event of a headlamp leveling motor fault, both headlamps are moved to the central position by means of the adaptive front lighting actuator motors and they remain in this position.
In the event of an adaptive front lighting actuator motor fault, the headlamp leveling motor moves the relevant headlamp to the lowest position where it remains. The intact headlamp is moved to the "0" position by the adaptive front lighting actuator motor.
For adaptive front lighting headlamps, adapting the vehicle to conform to country-specific traffic situations (left/right-hand side traffic) during travel is accomplished using a lever behind the headlamp cover, which is used to alter the headlamp beam.
To prevent oncoming traffic from being dazzled, the lever controls a shutter which partially blocks the headlight beams in order to produce symmetrically-shaped beams of light in low beam mode.
Adaptive front lighting module
The adaptive front lighting module, which is connected to the high-speed Controller Area Network (CAN), processes the CAN reverse gear switch, vehicle speed, light switch position and daytime running lamp signals as well as the steering angle sensor and headlamp leveling signals and sends control commands to the adaptive front lighting actuator motors and the headlamp leveling motors. The adaptive front lighting module must be configured with the WDS after renewal.
When the ignition and lights are switched on, the adaptive front lighting module performs calibration of the headlamps, during which both move inwards and then to the "0" position, independently of the steering wheel position. The headlamps only turn in the direction of cornering when the steering wheel is turned by more than 4°. Calibration is performed only once during an operating cycle (ignition key in position "2" and then in position "0").
Steering angle sensor
The rear lamp assemblies of wagon vehicles include all the rear lamp functions except the license plate lamp and high mounted stoplamp.
In 3-door and 5-door vehicles, the rear fog lamp, reversing lamp and reflectors are integrated in the rear bumper.
The rear lamp assemblies are replaced as a complete unit during servicing.
The rear lamp assemblies need to be removed in order to change a bulb.
The individual bulb holders and circuits are integrated in the bulb holder assembly in wagon and 4-door vehicles. In 3-door and 5-door vehicles this function is performed by the wiring harness.
In wagon and 4-door vehicles, a compact connector is used to connect the bulb holder with the wiring harness. In 3-door and 5-door vehicles, the wiring harness is connected to the bulb holder by means of two connectors.
The high mounted stoplamp is installed in the centre of the liftgate in wagon vehicles. In 3-door and 5-door vehicles it is installed in the rear spoiler and in 4-door vehicles it is installed in the headliner behind the rear window.
Peripheral lights
The purpose of peripheral lights is to illuminate the ground in the immediate vicinity of the front doors. The illumination is provided in the form of white bulbs which are located on the underside of the mirrors.
The peripheral lights are switched on when a door or the liftgate are opened or an unlock command is detected and the following conditions are fulfilled:
- The ignition key is in position "0" or "I".
- Reverse gear is not engaged.
- The vehicle speed is below 7 km/h.
Headlamp switch-off delay
In vehicles with mid to high-end equipment, the headlamp switch-off delay uses the low beams and the peripheral lights (if equipped) for illuminating the vehicle surroundings. The function is activated by operating the high beam lever when the ignition switch is in the "0" position.
After the last door has been closed, the function remains active for a further 30 seconds and then switches off automatically.
When a door or the liftgate is open, the switch-off time is extended to 180 seconds. After the last door has been closed, the switch-off time is reset to 30 seconds.
The headlamp switch-off delay can be deactivated prematurely by operating the high beam lever again or by switching on the ignition.
The s witch-off time is adjusted to set values at the factory and cannot be re-programmed using WDS.
