Lane Departure Warning

The purpose of the Lane Departure Warning with Haptic Feedback (LDW+) system is to provide a warning alert to the driver in case of an unintended lane departure (for example, the driver did not use turn signals beforehand to confirm a planned lane change).

The LDW+ system will retain the last system state (enabled or disabled) and the last lane warning sensitivity selected in the Radio from the last ignition cycle when the ignition is changed to the ON/RUN position.

The system can be overridden by the driver using a variety of methods, including turn signals, driver steering torque, steering torque rate, and acceleration and deceleration rate. The LDW+ system can also be turned ON or OFF with a single hard button on the Integrated Center Stack (ICS). The LED on the button will inform the driver of the system status when the driver is not on the driver assist screen in the Electronic Vehicle Information Center (EVIC). The feature will automatically disable when a safety system engages (such as traction control).

The main component of the LDW+ system is the forward facing camera. The camera mounts near the rear view mirror and communicates on the Controller Area Network - Chassis (CAN-C) bus. The camera also has a dedicated private CAN-B bus that connects directly to the radar sensor and that is used for Forward Collision Warning (FCW) and adaptive cruise control. The camera has the ability to detect alignment faults and is adjusted similar to the smart beam camera.

Another important factor in system operation is road condition. The Forward Facing Camera Module (FFCM) has the ability to detect the contrast of the surface of the pavement and the white or yellow lines. Roads that are not marked or that have extremely worn markings may not be detected by the camera which will disable the system. While monitoring the EVIC display for driver assist systems, a customer can tell if the system is enabled by the solid lines on the display. This is also important for diagnosing an intermittent or inoperative concern.

OPERATING CONDITIONS - LDW+ 

- The LDW+ system will be enabled and ready to provide feedback when the following conditions are met:

• The vehicle ignition is in the IGN_RUN state and the driver has enabled the system and reverse gear is NOT engaged.
• Supply voltage: within normal operating voltage range.
• No LDW+ system faults are present
• Vehicle speed is above 60 km/h (37 mph) and below 180 km/h (112 mph).
• The radius of curvature is within an allowable range.
• The vehicle's lateral acceleration is within an allowable range.
• Roads with positive or negative inclination transition (change in road grade) of up to 5%

OPERATING CONDITIONS - VISUAL ALERTS 

- The LDW+ system will be provide a visual alert when the following additional conditions have been met:

• A single (left or right) lane boundary is detected.
• The lateral velocity of the vehicle is within an allowable range.

OPERATING CONDITIONS - HAPTIC FEEDBACK WARNINGS 

- The LDW+ system will provide haptic feedback warning only when the following additional conditions have been met:

• Both left and right lane boundaries are detected.
• Minimum and maximum lane width is within an allowable range.
• No intervention of the safety systems Antilock Brake System (ABS), Electronic Stability Control (ESC) and Driver Assist System (DAS) Safety Requests (for example, Advanced Brake Assist (ABA), Adaptive Cruise Control (ACC) takeover request, FCW, and others). After the intervention of a safety system has ended, the LDW+ system can only provide haptic feedback warnings again after a calibrated period has been allowed to elapse.

OPERATION - Image Acquisition 

• In the daytime, the camera shall be able to detect lane markings where lighting and environmental conditions provide good visibility in excess of 30 meters.
• At night, the camera shall be able to detect lane markings with lighting conditions provided by standard, production low beam headlamps, with or without additional sources of road illumination, and where environmental conditions provide good visibility in excess of 30 meters.
• The camera is capable of compensating for sudden changes in lighting conditions such as during tunnel entry/exit.
• The LDW+ system will not have degraded performance from changes of the camera pitch angle due to vehicle dynamics (for example, during hard braking or acceleration) or under maximum rated vehicle loading conditions, for example, gross vehicle weight rating (GVWR).

OPERATION - FORWARD FACING CAMERA MODULE (FFCM) 

- The camera is able to detect lane marking of any color (especially yellow or white which are common colors for lane markings). The camera will detect and quantify the following information regarding the lane boundaries:

• The lateral distance from the center of the camera to the left lane boundary.
• The lateral distance from the center of the camera to the right lane boundary.
• The heading angle of the vehicle with respect to the center axis of the lane.
• A measurement of the radius of curvature of the road ahead of the vehicle.
• The type of lane boundary (double line, solid line, dashed line, road edge).

The camera is capable of self-monitoring the diagnosis to determine whether it is operating properly. The camera will detect if the camera lens is occluded and the windshield needs to be cleaned. During this condition, the indication will be provided to clean the windshield.

The system also monitors the torque sensor inside the Electric Power Steering (EPS) to verify the driver's hands remain on the wheel. If no driver's steering input is received, the system will deactivate until all enabling conditions are met. These Include:

• Drivers steering input.
• The FFCM can clearly detect the lines in the road.
• There are no Diagnostic Trouble Codes (DTC) present in the steering or LDW+ system.
• Vehicle speed is above 60 km/h (37 mph) and below 180 km/h (112 mph).

COMPONENT RESPONSIBILITY - BODY CONTROL MODULE (BCM) 

• Acquisition on the CAN-C bus of the LDW+ system enabled/disabled status from the FFCM to control the ICS LED indication.
• Acquisition on the CAN-C bus of the chime request from the FFCM to inform the driver to place his/her hands on the steering wheel.
• Acquisition on the CAN-C bus of the current LDW+ system sensitivity setting from the FFCM.
• Acquisition on the CAN-C bus of the current LDW+ system torque intensity setting from the FFCM.
• Acquisition on the LIN bus of the LDW+ system enable/disable switch (pressed/not pressed) status from the ICS.
• Gates the ICS on/off signal command on LIN to a signal on CAN-C.
• Gates the current ICS status signal on CAN-C to the BCM concerning an ICS control signal on the LIN bus.
• Transmission on the CAN-B bus of the chime request to the Radio to inform the driver to place his/her hands on the steering wheel (audible alert).
• Transmission on the CAN-B bus of the LDW+ system current sensitivity setting to the Radio.
• Transmission on the CAN-B bus of the LDW+ system current torque intensity setting to the Radio.
• Transmission on the CAN-C bus of the (left/right) turn signal lamp status to the FFCM.
• Transmission on the CAN-C bus of the wiper status (parked/not parked) to the FFCM.
• Transmission on the CAN-C bus of the reverse gear status to the FFCM.
• Transmission on the CAN-C bus of the vehicle configuration settings to the FFCM.
• Transmission on the CAN-C bus of the net configuration module options to the FFCM.
• Transmission on the CAN-C bus of the ignition status to the FFCM.
• Transmission on the CAN-C bus of the LDW+ system enable/disable request to the FFCM (gated from LIN).
• Transmission on the CAN-C bus of the LDW+ system sensitivity setting request (gated from CAN-B) to the FFCM.
• Transmission on the CAN-C bus of the LDW+ system torque intensity setting request (gated from CAN-B) to the FFCM.
• Transmission on the LIN bus of the LDW+ system enable/disable switch indicator control status to the ICS (gated from CAN-C).

COMPONENT RESPONSIBILITY - ELECTRONIC POWER STEERING (EPS) 

• Apply directional torque to the steering wheel as requested by the FFCM module during an unintentional lane departure.
• Manage the Torque Overlay Interface (TOI).
• Acquisition on the CAN-C bus of the torque overlay interface activation request from the FFCM.
• Acquisition on the CAN-C bus of the FFCM system status from the FFCM.
• Acquisition on the CAN-C bus of the FFCM drive style status from the FFCM.
• Transmission on the CAN-C bus of the FFCM TOI activation status to the FFCM.
• Transmission on the CAN-C bus of the FFCM TOI fault status to the FFCM.
• Transmission on the CAN-C bus of the EPS temporary deactivation status to the FFCM.
• Transmission on the CAN-C bus of the steering column torque to the FFCM.
• Transmission on the CAN-C bus of the steering column torque validity to the FFCM.
• Transmission on the CAN-C bus of the EPS motor torque to the FFCM.
• Transmission on the CAN-C bus of the EPS motor torque validity to the FFCM.

COMPONENT RESPONSIBILITY - FORWARD FACING CAMERA MODULE (FFCM) 

• Monitor the road scenario.
• Process the video image.
• Quantify the geometry of the lane boundaries in front of the vehicle.
• Calculate the torque request to control the vehicle response based on lane position of vehicle.
• Evaluate the "Hands Off" condition. When the driver's hands are not detected on the steering wheel, the system provides an audible warning consisting of left front and right front chimes to inform the driver to place his/her hands on the steering wheel.
• Acquisition on the CAN-C bus of the brake pedal status from the ESC.
• Acquisition on the CAN-C bus of the brake pedal status from the BCM.
• Acquisition on the CAN-C bus of the brake booster vacuum level from the ESC.
• Acquisition on the CAN-C bus of the (left/right) turn signal request status from the SCCM.
• Acquisition on the CAN-C bus of the (left/right) turn signal lamp status from the BCM.
• Acquisition on the CAN-C bus of the wiper status (parked/not parked) from the BCM.
• Acquisition on the CAN-C bus of the LDW+ system enable/disable request from the BCM.
• Acquisition on the CAN-C bus of the customer-selected LDW+ system sensitivity setting from the BCM.
• Acquisition on the CAN-C bus of the customer-selected LDW+ system torque intensity setting from the BCM.
• Acquisition on the CAN-C bus of the ignition status from the BCM.
• Acquisition on the CAN-C bus of the vehicle configuration settings from the BCM.
• Acquisition on the CAN-C bus of the net configuration module options from the BCM.
• Acquisition on the CAN-C bus of the transmission type from the PCM.
• Acquisition on the CAN-C bus of the ABS status from the ESC.
• Acquisition on the CAN-C bus of the ESC status from the ESC.
• Acquisition on the CAN-C bus of the ABS status from the BCM.
• Acquisition on the CAN-C bus of the ESC status from the BCM.
• Acquisition on the CAN-C bus of the DAS request active status from the ESC.
• Acquisition on the CAN-C bus of the DAS request active status from the BCM.
• Acquisition on the CAN-C bus of the vehicle speed from the ESC.
• Acquisition on the CAN-C bus of the yaw rate offset from the ESC.
• Acquisition on the CAN-C bus of the lateral acceleration offset from the ESC.
• Acquisition on the CAN-C bus of the longitudinal acceleration offset from the ESC.
• Acquisition on the CAN-C bus of the vehicle speed from the BCM.
• Acquisition on the CAN-C bus of the yaw rate offset from the BCM.
• Acquisition on the CAN-C bus of the lateral acceleration offset from the BCM.
• Acquisition on the CAN-C bus of the longitudinal acceleration offset from the BCM.
• Acquisition on the CAN-C bus of the ACC takeover request from the ACC module.
• Acquisition on the CAN-C bus of the Forward Collision Warning system status from the ACC module
• Acquisition on the CAN-C bus of the engine start/stop status from the ECM.
• Acquisition on the CAN-C bus of the gas pedal position from the PCM.
• Acquisition on the CAN-C bus of the reverse gear status from the ECM.
• Acquisition on the CAN-C bus of the steering angle from the EPS.
• Acquisition on the CAN-C bus of the steering angle rate from the EPS.
• Acquisition on the CAN-C bus of the DST TOI activation status from the EPS.
• Acquisition on the CAN-C bus of the reverse gear status from the BCM.
• Acquisition on the CAN-C bus of the Transmission Gear status from the PCM or TCM.
• Acquisition on the CAN-C bus of the steering angle from the SCCM.
• Acquisition on the CAN-C bus of the steering angle rate from the SCCM.
• Acquisition on the CAN-C bus of the effective torque applied on the steering wheel from the EPS.
• Acquisition on the CAN-C bus of the EPS motor torque from the EPS.
• Acquisition on the CAN-C bus of the FFCM TOI activation status from the EPS.
• Acquisition on the CAN-C bus of the FFCM TOI fault status from the EPS.
• Acquisition on the CAN-C bus of the EPS temporary deactivation status from the EPS.
• Acquisition on the CAN-C bus of the yaw rate from the ORC.
• Acquisition on the CAN-C bus of the lateral acceleration from the ORC.
• Acquisition on the CAN-C bus of the longitudinal acceleration from the ORC.
• Acquisition on the CAN-C bus of the yaw rate from the ESC.
• Acquisition on the CAN-C bus of the lateral acceleration from the ESC.
• Acquisition on the CAN-C bus of the longitudinal acceleration from the ESC.
• Acquisition on the CAN-C bus of the engine RPM from the PCM.
• Transmission on the CAN-C bus of the torque request to the EPS.
• Transmission on the CAN-C bus of the LDW+ system enabled/disabled status to the BCM.
• Transmission on the CAN-C bus of the chime request to the BCM (gateway) to inform the driver to place his/her hands on the steering wheel.
• Transmission on the CAN-C bus of the current LDW+ system sensitivity and torque intensity settings to the BCM and IPC.
• Transmission on the CAN-C bus of the LDW+ lane boundary detection status to the IPC.
• Transmission on the CAN-C bus of the LDW+ warning status to the IPC.
• Transmission on the CAN-C bus of the LDW+ ISO telltale status to the IPC.
• Transmission on the CAN-C bus of the LDW+ display popup status to the IPC.
• Transmission on the CAN-C bus of the LDW+ fault status to the IPC.

COMPONENT RESPONSIBILITY - ELECTRONIC STABILITY CONTROL (ESC) MODULE 

• ? Transmission on the CAN-C bus of the ABS status to the FFCM
• ? Transmission on the CAN-C bus of the brake pedal status to the FFCM
• ? Transmission on the CAN-C bus of the brake booster vacuum level to the FFCM
• ? Transmission on the CAN-C bus of the DAS request active status to the FFCM
• ? Transmission on the CAN-C bus of the vehicle speed to the FFCM
• ? Transmission on the CAN-C bus of the lateral acceleration to the FFCM
• ? Transmission on the CAN-C bus of the longitudinal acceleration to the FFCM
• ? Transmission on the CAN-C bus of the yaw rate to the FFCM
• ? Transmission on the CAN-C bus of the lateral acceleration offset to the FFCM
• ? Transmission on the CAN-C bus of the longitudinal acceleration offset to the FFCM
• ? Transmission on the CAN-C bus of the yaw rate offset to the FFCM

COMPONENT RESPONSIBILITY - INSTRUMENT PANEL CLUSTER (IPC) 

• Display LDW+ system state, configuration (sensitivity setting, torque intensity settting), lane boundary detection, warning and fault status.
• Acquisition on the CAN-C bus of the LDW+ lane boundary detection status from the FFCM.
• Acquisition on the CAN-C bus of the LDW+ warning status from the FFCM.
• Acquisition on the CAN-C bus of the LDW+ fault status from the FFCM.
• Acquisition on the CAN-C bus of the LDW+ ISO telltale status from the FFCM.
• Acquisition on the CAN-C bus of the LDW+ display popup status from the FFCM.
• Acquisition on the CAN-C bus of the current LDW+ system sensitivity setting from the FFCM.
• Acquisition on the CAN-C bus of the current LDW+ system torque intensity setting from the FFCM.
• Acquisition on the CAN-C bus of the vehicle configuration setting, for example, LDW present, from the BCM.

COMPONENT RESPONSIBILITY - INTEGRATED CENTER STACK (ICS) 

• Display LDW+ system defeat switch state (LED illuminated = LDW+ System OFF, or "defeated").
• Transmission on the CAN-C bus of the LDW+ system enable/disable switch (pressed/not pressed) status to the BCM
• Acquisition on the CAN-B bus of the LDW+ system enable/disable switch indicator control status from the BCM

COMPONENT RESPONSIBILITY - OCCUPANT RESTRAINT CONTROLLER (ORC) 

• Acquisition on the CAN-C bus of the torque request from the FFCM.
• Acquisition on the CAN-C bus of the torque overlay interface activation request from the FFCM.
• Acquisition on the CAN-C bus of the LDW+ warning status from the FFCM.
• Acquisition on the CAN-C bus of the LDW+ system enabled/disabled status from the FFCM.
• Acquisition on the CAN-C bus of the FFCM TOI activation status from the EPS.
• Acquisition on the CAN-C bus of the EPS motor torque from the EPS.
• Acquisition on the CAN-C bus of the EPS motor torque validity from the EPS.

COMPONENT RESPONSIBILITY - STEERING COLUMN CONTROL MODULE (SCCM) 

• ? Transmission on the CAN-C bus of the (left/right) turn signal lamp status to the FFCM
• ? Transmission on the CAN-C bus of the steering angle and steering angle rate to the FFCM

The hard wired circuits between components related to the LDW+ system may be diagnosed using conventional diagnostic tools and procedures. Refer to the appropriate wiring information. The wiring information includes wiring diagrams, details of wire harness routing and retention, connector pin-out information and location views for the various wire harness connectors, splices and grounds. For proper wire repair, and connector repair procedures. Refer to STANDARD PROCEDURE . and. Refer to REMOVAL . Refer to INSTALLATION . However, conventional diagnostic methods will not prove conclusive in the diagnosis of the LDW+ system or the electronic controls and communication between ECU and other devices that provide some features of this system. The most reliable, efficient and accurate means to diagnose the LDW+ system and related communication operation requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.