Lane Departure Warning System Malfunction
Lane Departure Warning System Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
Diagnostic Fault Information
Circuit/System Description
The lane departure warning is controlled by the frontview camera module mounted on the windshield. The lane departure warning is enabled and disabled through a switch located at the instrument panel. When enabled, the vehicle direction camera control module will illuminate the indicator located in the switch.
When the system is operating and can detect the lane markings, the vehicle direction camera control module will request via serial data communications that the instrument cluster illuminate the green lane departure ready-to-assist indicator. If the frontview camera module detects that the vehicle has crossed a lane marking without the turn signal being used, the module will request that the instrument cluster flash the yellow lane departure warning indicator. An audible warning will also sound three times when the yellow instrument cluster indicator is flashing.
Diagnostic Aids
Certain factors will affect the operation of the lane departure warning system. When the system is operating properly, the green lane departure indicator will illuminate on the instrument cluster. This indicates that all of the required operating conditions to permit lane departure warning have been met. The green lane departure indicator will not appear when the system is having difficulty seeing the lines on the road or if the view of the camera on the windshield is blocked with mud, dirt, snow, ice, or slush, if the windshield is damaged, or when weather limits visibility, such as while driving in fog, rain, or snow conditions. This is normal operation, the vehicle does not need service. Additionally, lane departure warnings may occasionally occur in a properly operating vehicle due to tar marks, shadows, cracks in the road, or other road imperfections. This is normal system operation and the vehicle does not require service. The driver information center may also display LANE DEPARTURE SYSTEM UNAVAILABLE due to the temporary conditions listed above.
Reference Information
Schematic Reference
Object Detection Schematics [1][2]Collision Avoidance and Parking Assist Systems
Connector End View Reference
Component Connector End Views Sunshade - Left
Description and Operation
Object Detection Description and Operation (Lane Departure Warning, UFL) Object Detection Description and Operation (Lane Departure Warning, UFL)Object Detection Description and Operation (Rear Vision Camera, UVC) Object Detection Description and Operation (Rear Vision Camera, UVC)Object Detection Description and Operation (Park Assist, UD7) Object Detection Description and Operation (Park Assist, UD7)Object Detection Description and Operation (Forward Collision Alert, UEU) Object Detection Description and Operation (Forward Collision Alert, UEU)
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Verification
1. Ignition ON.
2. Verify that DTC B356A is not set.
• If the DTC is set
Refer to DTC B356A B356A.
• If the DTC is not set
3. Verify that DTC B0987 is not set.
• If the DTC is set
Refer to DTC B0987 B0987.
• If the DTC is not set
4. Verify the scan tool Frontview Camera System Status parameter is Normal.
• If the parameter is Undefined or Malfunction
Refer to Circuit/System Testing.
• If the parameter is Normal
5. Verify the scan tool Lane Departure Warning Switch Status parameter changes between On and Off when pressing the lane departure warning switch.
• If the parameter does not change between On and Off
Refer to Lane Departure Warning Switch Circuit Malfunction in Circuit/System Testing.
• If the parameter changes between On and Off
6. All OK.
Circuit/System Testing
Lane Departure Warning Switch Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the S48D Multifunction Switch - Instrument Panel.
2. Test for less than 10 ohms between the ground circuit terminal 1 and ground.
• If 10 ohms or greater
1. Ignition OFF.
2. Test for less than 2 ohms in the ground circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the ground circuit.
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 10 ohms
3. Ignition ON.
4. Verify the scan tool Lane Departure Warning Switch parameter is Off.
• If not Off
1. Ignition OFF, disconnect the harness connector at the K109 Vehicle Camera Module.
2. Test for infinite resistance between the signal circuit terminal 4 and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance, replace the K109 Vehicle Camera Module.
• If Off
5. Install a 3 A fused jumper wire between the signal circuit terminal 4 and ground.
6. Verify the scan tool Lane Departure Warning Switch parameter is On.
• If not On
1. Ignition OFF, disconnect the harness connector at the K109 Vehicle Camera Module, ignition ON.
2. Test for less than 1 V between the signal circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V.
3. Test for less than 2 ohms in the signal circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K109 Vehicle Camera Module.
• If On
7. Test or replace the S48D Multifunction Switch - Instrument Panel.
Lane Departure Warning Switch Indicator Circuit Malfunction
1. Ignition OFF, disconnect the harness connector at the S48D Multifunction Switch - Instrument Panel.
2. Test for less than 10 ohms between the low control circuit terminal 8 and ground.
• If 10 ohms or greater
1. Ignition OFF.
2. Test for less than 2 ohms in the low control circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K109 Vehicle Camera Module.
• If less than 10 ohms
3. Ignition ON, test for 4.8-5.2 V between the voltage circuit terminal 3 and ground.
• If less than 4.8 V
1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module.
2. Test for infinite resistance between the voltage circuit and ground.
• If less than infinite resistance, repair the short to ground in the circuit.
• If infinite resistance
3. Test for less than 2 ohms in the voltage circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the K9 Body Control Module.
• If greater than 5.2 V
1. Ignition OFF, disconnect the harness connector at the K9 Body Control Module, ignition ON.
2. Test for less than 1 V between the voltage circuit and ground.
• If 1 V or greater, repair the short to voltage on the circuit.
• If less than 1 V, replace the K9 Body Control Module.
• If between 4.8-5.2 V
4. Test or replace the S48D Multifunction Switch - Instrument Panel.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
Control Module References Control Module References for Frontview Camera Module replacement, programming and setup