Pre-Collision (Diagnostics - Introduction): Other Lexus GS III рестайлинг

PRECAUTION

1. NOTICE FOR INITIALIZATION NOTE: When disconnecting the cable from the negative (-) battery terminal, initialize the following system after the terminal is reconnected. System Name See procedure Intuitive Parking Assist System Refer to «INITIALIZATION»(ref-386951-S21829001392011022400000) Theft Deterrent System Variable Gear Ratio Steering System
2. TROUBLESHOOTING PRECAUTIONS If a terminal contact point malfunction or part installation problem occurs, removal and reinstallation of the suspected part may return the system to normal. However, be aware that the normal condition may only be temporary. Before disconnecting connectors or removing / installing parts, determine the malfunctioning area by checking and writing down the vehicle's condition at the time of the malfunction (DTC outputs, etc.). Be sure to check for DTCs related to other systems. The pre-collision system may be influenced by malfunctions in other systems.
3. HANDLING PRECAUTIONS When removing and installing ECU, sensor, switch or other pre-collision system related parts, perform the following: Make sure the power switch is OFF unless otherwise specified in the inspection procedures. After the removal / installation, check for DTCs and confirm that a normal system code is output.

Scheme 6

Scheme 7

Scheme 8

COMMUNICATION TABLE

Scheme 9

1. PRE-COLLISION SYSTEM DESCRIPTION The pre-collision system optimizes and activates occupant protection equipment (see below) to attempt to reduce damage from collisions.
2. OUTLINE OF PRE-COLLISION SYSTEM Operating Condition Control Transmitting ECU Receiving ECU Part operated Operates according to sensor detection Pre-collision seat belts Cruise control ECU (distance control ECU) Seat belt control ECU Front seat outer belts Operates according to sensor detection Pre-collision brake assist Cruise control ECU (distance control ECU) Skid control ECU Brake assist system Operates according to sensor detection Damping force control Cruise control ECU (distance control ECU) Suspension control ECU Shock absorbers Operates when sudden braking occurs Pre-collision seat belts Skid control ECU Seat belt control ECU Front seat outer belts When operating according to sensor detection: The pre-collision sensor (millimeter wave radar sensor) detects vehicles and other objects on the road in front of the user's vehicle. The cruise control ECU (distance control ECU) determines if a collision is unavoidable based on object position, speed and track information. If the cruise control ECU determines that a collision is unavoidable, it transmits this information to the following areas through CAN communication: Seat belt control ECU (initiates control of pre-collision seat belts) Skid control ECU (activates pre-collision brake assist system) Suspension control ECU (tightens the suspension as much as possible) When operating as a result of sudden braking: The skid control ECU uses brake pressure information and other data to determine if the driver has suddenly applied the brakes. If so, the skid control ECU sends a signal to the seat belt control ECU through the CAN communication and the pre-collision seat belt activates.
3. OUTLINE OF PRE-COLLISION SEAT BELT CONTROL The pre-collision seat belt operates depending on what the sensor detects, or whether or not sudden braking has occurred. The pre-collision seat belt motor tightens the seat belt to optimize occupant restraint performance. Operative condition Refer to the sensor and sudden braking descriptions under "outline of pre-collision system" (see above).
4. OUTLINE OF PRE-COLLISION BRAKE ASSIST SYSTEM The pre-collision brake assist system operates depending on what the sensor detects. The system then enters standby mode before a collision. When the driver depresses the brake pedal, brake fluid pressure is increased to improve fluid pressure response and improve vehicle speed reduction rate. Operative condition Refer to the sensor description under "outline of pre-collision system" (see above). When the driver depresses the brake pedal after the cruise control ECU (distance control ECU) determines that a collision is unavoidable: Brake fluid pressure is increased at the same time the driver depresses the brake pedal. When the driver depresses the brake pedal before the cruise control ECU (distance control ECU) determines that a collision is unavoidable: Brake fluid pressure is increased at the same time that the cruise control ECU (distance control ECU) receives a pre-collision sensor signal (indicating that other vehicles or objects are in front of the vehicle).
5. OPERATIVE CONDITION AND INOPERATIVE CONDITION OF EACH CONTROL (REVIEW) Vehicle Condition Pre-collision seat belts*1 Pre-collision seat belts*2 Pre-collision brake assist*2 Power switch OFF or ON (ACC) - - - When warning message is displayed on multi-information display *3 *3 *3 When seat belt(s) is / are fastened *4 *4 o When own vehicle speed is 30 km/h or more, regardless of relative speed o - - When own vehicle speed is 5 km/h or more and relative speed is 30 km/h - o - When own vehicle speed is 30 km/h or more and relative speed is 30 km/h - - o When vehicle collides with object outside detection range of millimeter wave radar sensor (side collision, rear collision, etc.) *5 - - When millimeter wave radar sensor cannot detect possible collision object *5 - - HINT: *1: Operates when brakes are suddenly applied *2: Operates according to sensor detection *3: Inoperative parts are different depending on malfunction areas *4: Only operates when seat belt is fastened *5: Pre-collision seat belts may operate when brakes are suddenly applied
6. PRECAUTION FOR PRE-COLLISION SYSTEM OPERATION When the millimeter wave radar sensor detects an object in front of the vehicle under the conditions described below, the cruise control ECU (distance control ECU) may determine that a collision is unavoidable, and activate the pre-collision system. However, this is not abnormal. HINT: The pre-collision system will not activate when the pre-collision sensor detects safety cones and other plastic objects. The pre-collision system may or may not activate when the pre-collision sensor detects the following objects: people, bicycles, motorcycles, trees, animals and snow fences. Object Type Example Objects that cannot be detected Plastic items (safety cones) Objects that cannot be detected in a stable manner People, bicycles, motorcycles, trees, animals, snow fence, etc.

FAIL-SAFE CHART

HINT

The pre-collision system fail-safe function and details are indicated in the table below.

HINT

1. *1: The overheating prevention function operates when the seat belt control ECU detects a rise in seat belt control ECU temperature because of excessive seat belt operation.
2. *2: The pre-collision seat belts operate only with sudden braking.