Night View Assist, Function - GF54.30-P-0005FQ
MODEL 218
up to year 2015
with CODE 610 (Night view assist)
Up to 28.02.2013
As of 01.03.2013
Function requirements, general
- Terminal 15 ON
- Rain/light sensor detects "Twilight" or "Night" when exterior lights switch is in "A" or "Manual driving lights" position
- Vehicle in forward movement, speed v ≤ 260 km/h
- Low beams ON (for night mode)
The request to "switch on low beams" can only be issued with a circuit 15 ON status. The electronic ignition lock control unit sends the status of terminal 15 to the front SAM control unit over the interior CAN.
Night View Assist, general
The Night View Assist detects people and obstacles on the roadway and in the driver's field of view before they become visible in the conventional headlamp light cone. For this purpose, Night View Assist infrared camera 1 is located in the upper area of the windshield. This is designed for infrared light and records the path the road in front of the vehicle as soon as twilight sets in.
The detection range of Night View Assistant infrared camera 1 corresponds to the view through the windshield when the high beams are switched on. The image data from Night View Assist infrared camera 1 is processed by the Night View Assist control unit and then displayed on the Audio/COMMAND display.
Night View Assist infrared camera 1 operates like a conventional camera, but with an extended Infrared light spectrum. The picture data are therefore also displayed when the infrared illumination is not activated.
The windshield must be penetrable for infrared light in the field of view of Night View Assist infrared camera 1 (possible disturbing influences would be: fogging, blocking film, black print, adhesive label, stone chipping, icing up or dirt).
According to ambient brightness, the Night View Assist system differentiates between the following operating modes:
- Twilight mode
- Night mode
In twilight mode, the images recorded by Night View Assist infrared camera 1 are processed and then shown on the Audio/COMMAND display.
In night mode, as of a vehicle speed of v = 15 km/h the infrared lamps in the front lamp units are additionally switched on. The roadway in front of the vehicle is then illuminated with infrared light up to s = 150 m. Because infrared light is invisible to the human eye, oncoming traffic is not dazzled.
In addition, the Night View Assist system detects persons on or near the road surface outside built-up areas. The people detected are shown with highlighted edges in the Audio/COMMAND display. This function is called "Intelligent Night View" (night view with person detection). Pedestrian detection in front of the vehicle is possible up to a distance of s = 90 m.
Shown: "Intelligent Nightview" (night vision with pedestrian detection)
Function sequence for Night View Assist
Night View Assist is manually activated or deactivated by pressing the Night View Assist button on the exterior lights switch.
The front SAM control unit reads in the status of the Night View Assist button directly and sends the status to the COMMAND controller unit via the interior CAN and to the Night View Assist control unit via the chassis CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013). The COMMAND controller unit then activates the Audio/COMMAND display via the telematics CAN and switches the display to "Night View Assist image data". The image data captured by Night View Assist infrared camera 1 and processed by the Night View Assist control unit is then displayed on the Audio/COMMAND display. Night View Assist infrared camera 1 transmits the captured image data to the Night View Assist control unit via the digital video interface (LVDS line). The Night View Assist control unit processes the brightness distribution. Extremely bright picture areas that could dazzle the driver are thus filtered out here. The Night View Assist control unit then transmits the processed image data to the COMMAND controller unit via the analog video interface (direct line). The COMMAND controller unit then transmits this data to the Audio/COMMAND display via an additional digital video interface (LVDS line).
The displayed image area and the brightness of the display can be adjusted via the Audio/COMMAND control panel.
The Audio/COMMAND control panel sends the corresponding requests over the telematics CAN to the Audio/COMMAND display.
Night View Assist infrared camera 1 continuously captures the roadway in front of the vehicle and transmits the image data to the Night View Assist control unit. The Night View Assist control unit then checks the function requirements for display in the Audio/COMMAND display. The image data is only transmitted to the COMMAND controller unit when the Night View Assist is switched on and the function requirements are fulfilled. On vehicles up to 28.02.2013, the Night View Assist control unit additionally sends the status of the Night View Assist to the COMMAND controller unit via the chassis CAN, front SAM control unit and interior CAN. On vehicles as of 01.03.2013, the Night View Assist control unit sends the status of the Night View Assist to the COMMAND controller unit via chassis CAN 2, the front SAM control unit and interior CAN.
Display of the image data is, however, suppressed by the COMMAND controller unit under the following conditions:
- Engage reverse gear
- Application change (e.g. when operating the audio system or telephony)
The following input factors are read in and evaluated by the Night View Assist control unit:
- Ambient brightness
- Exterior lights status (low beams on in night mode)
- Vehicle speed
- Image data from Night View Assist infrared camera 1
- Light source detection (for person detection)
Ambient brightness and status of exterior lights:
The ambient brightness is sensed by the rain/light sensor. A distinction is made between the following brightness values:
- Daytime (Night View Assist not active)
- Twilight (twilight mode)
- Night-time (night mode)
The front SAM control unit reads in the data from the rain/light sensor via the wiper/inside mirror LIN and, as the master control unit for the exterior lights, checks the switch-on conditions for the infrared lights taking further parameters into consideration (e.g. status of the exterior lights).
The front SAM control unit then sends the result of this check as "Infrared light, status" to the Night View Assist control unit via the chassis CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013).
Vehicle speed:
The vehicle speed is calculated on the basis of the wheel speeds. On vehicles up to 28.02.2013, the Electronic Stability Program control unit sends the wheel speeds to the instrument cluster via the chassis CAN.
On vehicles as of 01.03.2013, the Electronic Stability Program control unit sends the wheel speeds to the instrument cluster via chassis CAN 1, the front SAM control unit and chassis CAN 2.
The instrument cluster calculates the vehicle speed to be displayed and sends it to the Night View Assist control unit and to the front SAM control unit via the chassis CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013).
Image data from Night View Assist infrared camera 1:
Night View Assist infrared camera 1 sends the image data to the Night View Assist control unit via the digital video interface (LVDS line).
After replacement of the windshield or a component of the Night View Assist, Night View Assist infrared camera 1 must be recalibrated.
Light source detection (for person detection):
The multifunction camera distinguishes between light sources on vehicles and static light sources (e.g. street lamps). If the multifunction camera identifies static light sources in the vehicle's surroundings, the "Intelligent Night View" function is deactivated. For this purpose, the multifunction camera sends corresponding information to the Night View Assist control unit via the chassis CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013).
The Night View Assist control unit evaluates all the relevant data and switches between twilight and night modes depending on the ambient brightness.
In night mode, the Night View Assist control unit generates the "Infrared lights ON" request and, on vehicles up to 28.02.2013, sends it to the headlamp control units via the chassis CAN, front SAM control unit and front-end CAN. On vehicles as of 01.03.2013, the Night View Assist control unit sends the "Infrared lights ON" request to the headlamp control units via chassis CAN 2.
The left headlamp control unit sends the "Infrared lights ON" request via the left headlamp LIN to left front exterior lighting LED actuation module 1, which then actuates the left infrared light. The right headlamp control unit sends the "Infrared lights ON" request via the right headlamp LIN to right front exterior lighting LED actuation module 1, which then actuates the right infrared light. Front exterior lighting LED actuation modules 1 actuate front lamp unit fan motors 1. This prevents the LEDs and the plastic housings of the front lamp units from overheating as a result of high outside temperatures and/or high actuation currents. The front exterior lighting LED actuation modules 1 send the status of the infrared lights to the respective headlamp control unit via the headlamp LIN. The headlamp control units send the status of the infrared lights to the front SAM control unit via the front end CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013).
The front exterior lighting LED actuation modules 1 monitor operation of the infrared lights. In the event of malfunctions, front exterior lighting LED actuation modules 1 send corresponding information to the headlamp control units via the headlamp LIN. The headlamp control units then send this information to the front SAM control unit via the front-end CAN (28.02.2013) or chassis CAN 2 (as of 01.03.2013).
If the vehicle speed drops below v = 5 km/h, the infrared lights are switched off.
The manual function test on the infrared lights is only possible with the diagnostic tester and only for approx. t = 10 s. For this purpose, a white surface (e.g. a piece of white paper) has to be held in front of the infrared lamps. When observed from the side, a red-green shimmer can be seen on the white surface. A repeat of the function test is then only possible after t = 5 min.
When the Night View Assist system detects people on or near the road surface in night mode, these are highlighted with edges and displayed on the Audio/COMMAND display. For this it has to be defined whether the vehicle is in a town or on a non-illuminated country road. This is accomplished by evaluating the data from the multifunction camera (light source detection).
Function notes:
Due to the limits of the system, the pedestrian detection function may interpret incorrectly, e.g. objects may be perceived as persons and displayed with highlighted edges.
The identification rate drops off with increasingly unfavorable conditions (e.g. strong backlighting, rain, snow, bright background or very darkly clothed people). Persons are then no longer shown highlighted.
Malfunctions of the Night View Assist system are communicated to the driver via the multifunction display. Here, a distinction is made between user-related and system-related messages. The Night View Assist control unit sends corresponding requests to the instrument cluster via the chassis CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013).
The messages listed in the tables below are sent by the Night View Assist control unit to the instrument cluster via the chassis CAN (up to 28.02.2013) or chassis CAN 2 (as of 01.03.2013).
| User-related messages | Meaning |
|---|---|
| "Night View Assist not in gear range R" | Gear range "R" is engaged |
| "Night View Assist lights ON or AUTO not in gear range R" | Gear range "R" is engaged, Rotary light switch not in position "A" or "Manual driving lights" |
| "Night View Assist lights ON or AUTO" | Rotary light switch not in position "A" or "Manual driving lights" |
| "Night View Assist no display over x km/h" | Speed over v = 260 km/h |
| System-related messages | Meaning |
|---|---|
| "Night View Assist is being started" | Night View Assist system is being initialized |
| "Night View Assist inoperative" | Faulty connection in the analog video interface, Faulty CAN communication, Infrared lights defective |
| "Night View Assist not currently available" | Night View Assist infrared camera 1 shut off due to overheating Temporary interruption along control or data line of Night View Assist infrared camera 1 |
| "Night View Assist only when it is dark" | Rain/light sensor transmits "day" Rain/light sensor defective Faulty connection of rain/light sensor |
| "Night View Assist available again" | Temporary source of fault has been eliminated |
| Electrical function schematic, Night View Assist | Model 218 up to model year 2014 with code 610 (Night view assist) | PE54.30-P-2053-97XAA | |
| Electrical function schematic, Night View Assist | Model 218 as of model year 2014 up to model year 2015 with code 610 (Night view assist) | PE54.30-P-2053-97XAB | |
| Overview of system components for driver assistance systems | GF54.00-P-9998FQ |