GF54.30-P-0005LE Night View Assist, Function

GF54.30-P-0005LE Night View Assist, Function
- with CODE (610) Night vision assist
- as of model year 09

Function requirements, general
^ Speed v ≤260 km/h (forward travel)
^ Rain/light sensor (B38/2) detects twilight or night
^ Low beams on (daytime running lights active or rotary light switch (S1) in "manual driving lights" position or "auto") (in night mode)

The request to "switch on low beams" can only be issued with circuit status circuit 15 ON. The electronic ignition lock control unit (N73) transmits the circuit 15 status to the front SAM control unit with fuse and relay module (N10/1) via the interior CAN (CAN B)

System messages with unfulfilled function requirements:
- "Night View Assist light ON or AUTO"
- Rotary light switch in position "0

- "Night View Assist only when it is dark"
- Rain/light sensor transmits "day"

Night View Assist, general
The Night View Assist system serves to visualize the road in front of the vehicle during darkness with the aim of detecting obstacles before they can be rendered visible by conventional headlamps.

The Night View Assist camera (B84/2) mounted in the area of the rain/light sensor records the road, then processes the information and shows it on the multifunction display (A1p13) of the instrument cluster (A1).
In addition, the route is illuminated with infrared light at night and at a vehicle speed of v > 10 km/h.

The picture recorded by the system corresponds to the view through the windshield with the high beams switched on. Infrared light is invisible to the human eye. Oncoming traffic is thus not dazzled.

Component Identification:

The master control unit of the Night View Assist system is the Night View Assist control unit (N101). This processes all relevant information, assesses it and controls the output of pictures taken by the Night View Assist camera in the multifunction display of the instrument cluster.

Vehicles up to 31.5.09: The Night View Assist control unit is a subscriber to the vehicle dynamics CAN (CAN H). All relevant information is read in by the ESP control unit (N47-5) via the chassis CAN (CAN E) and forwarded to the Night View Assist control unit.

Vehicles as of 1.6.09: The Night View Assist control unit is a subscriber to the chassis CAN.
Person detection functionality has been added to the Night View Assist system on model 221, so individuals who are moving on dark roads outside the city limits may be identified.

This functionality is called "Intelligent Nightview" (night view with person detection). The identified people are displayed with highlighted edges in the multifunction display. Person detection is possible up to a distance of s = 90 m in front of the vehicle.

Component Identification:

According to ambient brightness, the Night View Assist system differentiates between the following operating modes:
- Twilight mode
- Night mode

In twilight mode, pictures taken by the Night View Assist camera are shown in the multifunction display.

Additionally, in night mode, the left infrared lamp (E1e11) is activated in the left front lamp unit (E1) and the right infrared lamp (E2e11) is activated in the right front lamp unit (E2). The road in front of the vehicle is then illuminated with infrared light up to s = 150 m.

H11 halogen lamps with filters to filter out visible light are used to generate the infrared light. The heat development of the infrared lamp is equivalent to that of a normal high beam.

The infrared light function test is carried out using an IS tester and is possible for approx. t = 10 s. Hold a white surface (e.g. a piece of white paper) in front of the infrared lamp for this. When observed from the side, a red-green shimmer can be seen on the white surface. A repeat of the function test is only possible after t = 5 min.

Function sequence for Night View Assist
The Night View Assist control unit evaluates the following information:
- Night View Assist button status (S1s9)
- Rain/light sensor data
- Low beams activation status
- Wheel speeds, vehicle speed
- Vehicle dynamics (as of 1.6.09)
- Status of reverse gear

The Night View Assist system is activated manually by pressing the Night View Assist button. The Night View Assist button status is read in by the upper control panel control unit (N72/1) via the instrument panel (LIN 1), placed on the interior CAN and made available on the chassis CAN and the central CAN (CAN F) by the central gateway control unit (N93). The instrument cluster reads in the Night View Assist button status and replaces the standard display of the electronic speedometer with a bar graph display with video image.

Vehicles up to 31.5.09:
The ESP control unit reads in the Night View Assist button status and relays this to the Night View Assist control unit via the vehicle dynamics CAN.

Vehicles as of 1.6.09:
The Night View Assist control unit reads in the Night View Assist button status via the chassis CAN.

The ambient brightness is recorded by the rain/light sensor. A distinction is made between the following brightness values:
- Day: Night View Assist system disabled
- Twilight: Twilight mode (Night View Assist display activated)
- Night: Night View Assist fully activated (additional infrared lamps active)

Switching between the modes takes place after the rain/light sensor data has been evaluated. These are read in by the overhead control panel control unit (N70) and placed on the interior CAN. The central gateway control unit places these on the chassis CAN.

Vehicles up to 31.5.09:
The ESP control unit reads in the rain/light sensor data and transmits these via the chassis CAN to the Night View Assist control unit.

Vehicles as of 1.6.09: independently
The Night View Assist control unit reads in the rain/light sensor data via the chassis CAN.

The master control unit for the exterior lights is the front SAM control unit, which places the "low beams actuation active" status on the interior CAN. The central gateway control unit relays this to the chassis CAN.

Vehicles up to 31.5.09:
The ESP control unit reads in the "low beam actuation active" status and transmits this via the vehicle dynamics CAN to the Night View Assist control unit.

Vehicles as of 1.6.09:
The Night View Assist control unit reads in the "low beam actuation active" status via the chassis CAN.

The vehicle speed is calculated on the basis of the wheel speeds. The wheel speeds are recorded by the following components:
- Left front rpm sensor (L6/1)
- Right front rpm sensor (L6/2)
- Left rear rpm sensor (L6/3)
- Right rear rpm sensor (L6/4)

The ESP control unit (without model 221.095/195) or the regenerative braking system control unit (N30/6) (model 221.095/195) reads in the rpm sensor signals and transmits these via the chassis CAN to the central gateway control unit. The central gateway control unit relays the signals via the central CAN to the instrument cluster.

In addition, the signals from the rpm sensors are provided to the Night View Assist control unit via the vehicle dynamics CAN on vehicles up to 31.5.09 and via the chassis CAN on vehicles as of 1.6.09.

The instrument cluster calculates the vehicle speeds for display and places these on the central CAN. The central gateway control unit then places this information on the chassis CAN.

Vehicles up to 31.5.09:
The ESP control unit reads in the information for vehicle speed and transmits this via the vehicle dynamics CAN to the Night View Assist control unit.

Vehicles as of 1.6.09:
The Night View Assist control unit reads in the information on the vehicle speed via the chassis CAN.

Additionally, on vehicles as of 1.6.09, the Night View Assist control unit analyzes the following information on the natural dynamics of the vehicle:
- Yaw characteristics of the vehicle
- Rotation angle and steering angle rate of change

The steering angle and the steering angle rate of change are recorded by the steering angle sensor (N49) and made available on the chassis CAN by the steering column tube module (N80). The yaw rate sensor for lateral and longitudinal acceleration (B24/15) transmits information about the vehicle's yaw characteristics via the vehicle dynamics CAN to the ESP control unit or to the regenerative braking system control unit, which relays this via the chassis CAN to the Night View Assist control unit. The information on the natural dynamics of the vehicle is used to predict the movement of the vehicle.

The pictures taken by the Night View Assist camera are displayed in the multifunction display once the speed threshold of v = 10 km/h is reached.
The Night View Assist camera transmits these via a digital video interface (Low Voltage Differential Signal (LVDS)) to the Night View Assist control unit. The Night View Assist control unit receives the data from the Night View Assist camera and prepares these for output in the multifunction display.

The Night View Assist camera operates like a conventional camera, but with an extended infrared light spectrum. For this reason, the video image is displayed even when the infrared lamps are not active.
After replacing the windshield, a component of the Night View Assist system or the removal of the Night View Assist camera, the Night View Assist camera must be recalibrated.

The Night View Assist control unit filters out extremely bright areas of the image, which could blind the driver. This makes it easier for the driver to see the relevant content of the picture (e.g. obstacles, pedestrians or cyclists). The light spread is assessed in the Night View Assist control unit.

The windshield must be allow infrared light to pass through in the field of view of the Night View Assist camera (possible negative influences are: barrier sheets, black print, labels, stone chipping, ice or dirt).

The Night View Assist control unit transmits the processed data via the digital video interface (LVDS line) to the instrument cluster. The multifunction display replaces the standard display of the electronic speedometer with a bar graph display with video image.

In night mode, the front SAM control unit also actuates the infrared lamps. The request to switch on the infrared lamps is issued by the Night View Assist control unit.

The actuation of the infrared lamps is disabled at vehicle speeds of v < 5 km/h.

Vehicles up to 31.5.09:
The Night View Assist control unit transmits the request to activate the infrared lamps via:
- Vehicle dynamics CAN
- ESP control unit,
- Chassis CAN
- Central gateway control unit
- Interior CAN
- Front SAM control unit

Vehicles as of 1.6.09:
independently The Night View Assist control unit transmits the request to activate the infrared lamps via:
- Chassis CAN
- Central gateway control unit
- Interior CAN
- Front SAM control unit

Model 221 as of 1.6.09:
If the Night View Assist system identifies individuals in the field of view of the Night View Assist camera during night mode, they are shown with highlighted edges in the multifunction display. For this purpose, it is necessary to define whether the vehicle is located in a city or on an unlit road. This is accomplished by evaluating the data from the multifunction camera (A40/11).
The multifunction camera differentiates between light sources originating from one's own vehicle and surrounding light sources (e.g. street lamps).

If the multifunction camera identifies light sources not originating from the vehicle in the vehicle surroundings, person detection is disabled.
For this purpose, the multifunction camera transmits corresponding information via the chassis CAN to the Night View Assist control unit.

Because of the way the person detection system works, misinterpretations can occur, e.g. objects are perceived as individuals and shown 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) and individuals are not shown highlighted.

The display of pictures taken by the Night View Assist camera in the multifunction display is disabled under the following conditions:
- Exceeding or falling below the vehicle speed range
- Engaging the reverse gear

When reverse gear is engaged, the night vision display in the multifunction display is replaced with the standard display of the electronic speedometer.

Engaging the reverse gear is defined by the corresponding transmission gearshift position.
The transmission gearshift position status is made available by the intelligent servo module for DIRECT SELECT (A80) on the drive train CAN (CAN C) and is relayed by the CDI control unit (N3/9) (with diesel engine) or ME-SFI [ME] control unit (N3/10) (with gasoline engine) on the chassis CAN.

Vehicles up to 31.5.09:
The ESP control unit reads in the transmission gearshift position status and transmits this via the vehicle dynamics CAN to the Night View Assist control unit.

Vehicles as of 1.6.09: independently
The Night View Assist control unit reads in the transmission gearshift position status via the chassis CAN.

The Night View Assist control unit then interrupts the transmission of pictures to the instrument cluster.

System messages:
- Black background instead of the night vision display:
- Discontinuity in the LVDS line

- "Night View Assist is being started":
- Night View Assist system is being initialized

- "Night View Assist inoperative":
- Faulty connection of the LVDS line
- Faulty CAN connection
- Infrared lamps out of operation

- "Night View Assist not currently available":
- Faulty connection of the LVDS line
- Faulty CAN connection
- Infrared lamps out of operation

- "Night View Assist only when it is dark":
- Rain/light sensor transmits "day"
- Defective rain/light sensor
- Faulty connection of the rain/light sensor

- "Night View Assist not in gear range R":
- "R" gear range is engaged

- "Night View Assist Lights ON or AUTO Not in gear range R":
- "R" gear range is engaged
- Rotary light switch in position "OFF"

- "Night View Assist light ON or AUTO":
- Rotary light switch in position "OFF"

- "Night View Assist no display over x km/h":
- Speed over v = 260 km/h

- "Night View Assist no display in gear range R":
- "R" gear range engaged (rotary light switch "ON")

- "Night View Assist available again":
- Source of faults have been removed