LANE DEPARTURE PREVENTION (LDP) SYSTEM : System Description

SYSTEM DIAGRAM

Fig 1: Lane Departure Prevention - System Diagram

Courtesy of NISSAN MOTOR CO., U.S.A.

ADAS CONTROL UNIT INPUT/OUTPUT SIGNAL ITEM

Input Signal Item

Output Signal Item

FUNCTION DESCRIPTION

• Lane Departure Prevention (LDP) system provides a lane departure warning and brake control assistance when the vehicle is driven at speeds of approximately 70 km/h (45 MPH) or more.
• When the vehicle approaches either the left or the right side of the traveling lane, a warning sounds and the lane departure warning lamp (yellow) on the combination meter blinks to alert the driver. Then, the LDP system automatically applies the brakes for a short period of time to help assist the driver to return the vehicle to the center of the traveling lane.
• Warning and brake control are not performed during turn signal operation (lane change side).
• The warning and assist functions stop when the vehicle returns to a position inside of the lane marker.

EXAMPLE

Fig 2: Identifying Lane Departure Prevention (Example)

Courtesy of NISSAN MOTOR CO., U.S.A.

When the vehicle approaches the right lane marker, the driver is alerted by the buzzer and the blinking of lane departure warning lamp (yellow). Simultaneously, the left brake is controlled independently to generate force toward the direction to recover the vehicle from the lane departure.

OPERATION DESCRIPTION

• When the system is turned ON by dynamic driver assistance switch, ADAS control unit transmits LDP ON indicator signal to combination meter via CAN communication.
• Lane camera unit monitors lane markers of the traveling lane. It transmits the detected lane condition signal to ADAS control unit via ITS communication.
• When judging from a lane marker detection signal that the vehicle is approaching the lane marker, ADAS control unit controls the following items.
  • Activates warning buzzer.
  • Transmits a lane departure warning lamp signal to combination meter via CAN communication.
  • Calculates necessary yaw moment to transmit a target yaw moment signal to ABS actuator and electric unit (control unit) via CAN communication.
• When receiving the target yaw moment signal, ABS actuator and electric unit (control unit) controls brake pressure of four wheels, respectively.
• When receiving the signal from ADAS control unit, combination meter turns ON/OFF the lane departure warning lamp (yellow) and the LDP ON indicator lamp (green).

OPERATING CONDITION

• LDP ON indicator lamp: ON
• Vehicle speed: approximately 70 km/h (45 MPH) or more
• Turn indicator signal: After 2 seconds or more from turned OFF
  NOTE:

  • When the LDP system setting on the navigation screen is ON.
  • After the operating conditions are satisfied, the control continues until the vehicle speed reaches approximately 60 km/h (40 MPH).
  • The LDP system may not function properly, depending on the situation. Refer to "PRECAUTIONS FOR LANE DEPARTURE WARNING/LANE DEPARTURE PREVENTION ".

Bulb Check Action and Fail-safe Indication

Vehicle condition/Driver's operation	Indication on the combination meter	Buzzer
Ignition switch OFF ==> ON (Bulb check)	Courtesy of NISSAN MOTOR CO., U.S.A.	-
When DTC is detected (Except "C1B01" and "C1B03")	Courtesy of NISSAN MOTOR CO., U.S.A.	Beep
Camera aiming is not completed ("C1B01" is detected) NOTE: This is detected while driving the vehicle and the indication remains ON until the ignition switch is turned OFF
Temporary disabled status at high temperature ("C1B03" is detected)	Courtesy of NISSAN MOTOR CO., U.S.A.	Beep
When the dynamic driver assistance switch is pressed [When the settings of LDP system, DCA system on the navigation screen are both "OFF"]	Courtesy of NISSAN MOTOR CO., U.S.A.	-