Pre-Collision System (Diagnostics - Introduction): Other Lexus IS III

PRECAUTION [04/2013 - ]

1. PRECAUTION FOR DISCONNECTING CABLE FROM NEGATIVE BATTERY TERMINAL NOTE: When disconnecting the cable from the negative (-) battery terminal, initialize the following system after the cable is reconnected. System Name See Procedure Air Conditioning System Refer to «INITIALIZATION [04/2013 - ]»(ref-665529-S01115916402014102400000) 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 condition at the time the malfunction occurred (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 ECUs, sensors, switches or other pre-collision system related parts, perform the following: Make sure that the engine switch is off unless otherwise specified in the inspection procedure. After removal/installation, check for DTCs and confirm that a normal system code is output.

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COMMUNICATION TABLE

1. *: w/ Adaptive Variable Suspension System

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1. PRE-COLLISION SYSTEM The pre-collision system detects vehicles and obstacles in front of the vehicle and performs the following: 1) optimally uses system controls to avoid collisions, and 2) uses system controls to reduce impact during a collision. The operation of this system can be disabled by the pre-collision system cancel switch assembly. HINT: While the pre-collision system is disabled, the PCS warning indicator on the combination meter assembly is illuminated. The operation of the pre-collision brake assist, pre-collision brake control and suspension control* can be disabled by the combination switch assembly (VSC OFF switch). HINT: When the pre-collision brake assist control, pre-collision brake control and suspension control* are disabled, the multi-information display will display "VSC System Switched Off. Pre-Collision Brake System Disengaged." for 6 seconds and the PCS warning indicator on the combination meter assembly illuminates. *: w/ Adaptive Variable Suspension System
2. OUTLINE OF PRE-COLLISION SYSTEM Operating Condition Control Transmitting ECU Receiving ECU Part Operated Collision is possible Pre-collision alarm Driving Support ECU Assembly Combination meter assembly (warning message) Millimeter wave radar sensor assembly (warning buzzer) Combination meter assembly (warning message) Skid control buzzer assembly (warning buzzer) Collision is possible Pre-collision brake assist Driving Support ECU Assembly Brake actuator assembly (skid control ECU) Brake system Collision is unavoidable Pre-collision brake Driving Support ECU Assembly Brake actuator assembly (skid control ECU) Brake system Collision is possible Suspension control* Driving Support ECU Assembly Absorber control ECU Shock absorber *: w/ Adaptive Variable Suspension System When operating according to millimeter wave radar sensor assembly detection: The millimeter wave radar sensor assembly detects vehicles and other objects on the road in front of the user's vehicle. The driving support ECU assembly determines if the possibility of a collision is high or if a collision is unavoidable based on object position, speed and track information. If the driving support ECU assembly determines that the possibility of collision is high or that a collision is unavoidable, it transmits this information to the following areas via CAN communication: Combination meter assembly (warning message) (activates pre-collision alarm) Millimeter wave radar sensor assembly (warning buzzer) (activates pre-collision alarm) Brake actuator assembly (skid control ECU) (activates pre-collision brake assist) Brake actuator assembly (skid control ECU) (activates pre-collision brake) Absorber control ECU (activates suspension control)* *: w/ Adaptive Variable Suspension System
3. OUTLINE OF PRE-COLLISION ALARM When the system determines that there is a high possibility of colliding with an obstacle in front of the vehicle, the multi-information display and warning buzzer are used to warn the driver and help with collision avoidance.
4. OUTLINE OF PRE-COLLISION BRAKE ASSIST CONTROL The pre-collision brake assist operates depending on what the millimeter wave radar sensor assembly 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 the rate of deceleration. Operating conditions Refer to the millimeter wave radar sensor assembly description under "Outline of Pre-collision System" (see above). When the driver depresses the brake pedal after the driving support ECU assembly determines that the possibility of a collision is high: Brake fluid pressure is increased at the same time the driver depresses the brake pedal.
5. OUTLINE OF PRE-COLLISION BRAKE CONTROL The pre-collision brake operation is performed depending on what the millimeter wave radar sensor assembly detects. Operating conditions Refer to the millimeter wave radar sensor assembly description under "Outline of Pre-collision System" (see above). When the driving support ECU assembly determines that a collision is unavoidable, the system performs brake control (pre-collision brake operation) to reduce the vehicle speed. When a preceding vehicle is detected, the system advances brake control (pre-collision brake operation) activation timing in order to increase speed reduction performance.
6. OUTLINE OF SUSPENSION CONTROL (w/ Adaptive Variable Suspension System) When it is determined that there is a high possibility of colliding with an obstacle in front of the vehicle, the adaptive variable suspension system is operated to control the damping force, suppress nose diving and rolling, and support collision avoidance through steering.
7. OPERATIVE CONDITION AND INOPERATIVE CONDITION OF EACH CONTROL (REVIEW) HINT: Each function will operate when all items marked (o) are satisfied. - Pre-collision Alarm Pre-collision Brake Assist Pre-collision Brake Suspension Control*1 Engine switch is on (IG) o o o o When warning message is not displayed on multi-information display *2 *2 *2 *2 Operates when the vehicle speed is 15 km/h (10 mph) or more and relative speed is 15 km/h (10 mph) or more o x o x Operates when the vehicle speed is 5 km/h (4 mph) or more and relative speed is 30 km/h (19 mph) or more x x x o Operates when the vehicle speed is 30 km/h (19 mph) or more and relative speed is 30 km/h (19 mph) or more x o x x When pre-collision system cancel switch assembly is not turned on o o o o When combination switch assembly (VSC OFF switch) is not push in x o o o o: Operation conditions are included x: Not operation conditions are included *1: w/ Adaptive Variable Suspension System *2: Inoperative parts differ depending on malfunction areas
8. CASES OF UNNECESSARY PRE-COLLISION SYSTEM OPERATION When the millimeter wave radar sensor assembly detects an object in front of the vehicle under the following conditions, the driving support ECU assembly may determine that the possibility of a collision is high or a collision is unavoidable, and activate the pre-collision system. This activation of the system is not abnormal. *a There are objects on the side of the road at the beginning of a curve (a guardrail, street lamp, billboard, etc.). *b Passing an oncoming vehicle on a curve. *c There is an oncoming vehicle when making a left turn. *d Crossing a narrow metal bridge. *e There are metal objects on the road. *f Approaching a leading vehicle suddenly. *g Approaching an electrical toll collection gate (reacts to bar). *h Crossing an overpass, traffic sign, signboard. *i The vehicle height drastically changes (nose-up, nose-down). *j Misalignment of millimeter wave radar sensor assembly (reinstallation, collision, etc.). *k There is a billboard or sign at the top of an incline. *l There are metal objects at the bottom of a decline (a metal plate covering road construction, a mesh drain cover, a manhole, etc.). *m Roughness in road surface. *n When driving under an overpass *o When passing through a tunnel - - HINT: The pre-collision system will not activate when approaching safety cones or other plastic objects as they cannot be detected by the millimeter wave radar sensor assembly. The pre-collision system may or may not activate when the millimeter wave radar sensor assembly detects the following objects: people, bicycles, motorcycles, trees, animals, snow fences, etc. Detection performance may deteriorate under the following conditions. On a tight curve or bumpy road Something or someone suddenly emerges in the direction of travel of the driver's vehicle at a place such as an intersection Another vehicle suddenly cuts in the traveling direction of the driver's own vehicle In severe weather such as heavy rain, fog, snow or a sand storm Vehicle is skidding sideways while the vehicle stability control system is not operating Vehicle height changes significantly (front of vehicle inclined either upward or downward) Millimeter wave radar sensor assembly is misaligned (due to reinstallation or collision) 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 fences, etc.

CAUTION / NOTICE / HINT

HINT

1. Use the following procedure to troubleshoot the pre-collision system.
2. *: Use the Techstream.

Scheme 35

1. VEHICLE BROUGHT TO WORKSHOP Result Proceed to NEXT Result: 1 NEXT See step 2
2. CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK Pre-collision System Customer Problem Analysis Vehicle Brought to Workshop Year Month Day Name Registration No. - First Registered Year - Vehicle Model - Frame No. - Customer Concerns Problem symptoms first occurred Year Month Day Approx. Time Frequency of problem symptoms Continuously / Occasionally (times per day, times per month) / Only Once Weather Sunny / Cloudy / Rain / Snow / Other () Temperature About °C (°F) Place Prefecture Conditions Urban area / Suburbs / Highway / Other () Conditions Direction of travel Straight / Right turn / Left turn / Right curve / Left curve Driving lane Number of lanes on one side (lanes) / () lane(s) from left Lane width m - Details of driving conditions at time of occurrence (driving lane, driving route, position and type of surrounding vehicles, etc.) *Please include detailed diagram on Additional Customer Problem Analysis Sheet Preceding vehicle Y / N - Vehicle running parallel Y / N Following vehicle Y / N Parked vehicles nearby Y / N Construction Y / N Road obstructions Signs / Manhole / Guardrails / Other () Vehicle speed km/h - Automatic brakes operated Unknown / Y / N Seat belts tightened Unknown / Y / N Intelligent headrest operated Unknown / Y / N Pre-collision seat back operated Unknown / Y / N Hazard warning light blinking Unknown / Y / N PCS indicator Unknown / Y / N Information display Unknown / No display / "Brake!" message / " Check PCS System " message / " PCS temporarily not available " message / Other () Buzzer sounding Unknown / Yes (long beep) / Yes (short beeps) / None Vehicle Inspection Items Tire pressure Front: LH () kPa RH () kPa Standard () kPa Rear: LH () kPa RH () kPa Standard () kPa Vehicle height () mm Standard () mm * Refer to "WHEEL ALIGNMENT ADJUSTMENT" in Service Information Front millimeter wave radar sensor beam axis Vertical direction () Standard: 0.2° upwards Horizontal direction () Standard: 0° Rear millimeter wave radar sensor beam axis Vertical direction () Standard: 0.2° upwards Horizontal direction () Standard: 0° Front millimeter wave radar sensor RH beam axis Vertical direction () Standard: 0.2° upwards Horizontal direction () Standard: 0° Front millimeter wave radar sensor LH beam axis Vertical direction () Standard: 0.2° upwards Horizontal direction () Standard: 0° History of repairs around radar sensor Yes (FR / RR / RH / LH) / No Retrieval of Vehicle Control History Complete / Incomplete (Retrieval necessary) / Not equipped DTC / DATA LIST First time (when vehicle brought to workshop) - Second time (after DTCs cleared) - History of dirt on rear radar sensor Y / N Front radar sensor high temperature history Y / N History of dirt on front radar sensor Y / N Rear radar sensor high temperature history Y / N History of dirt on front radar sensor RH Y / N Front radar sensor RH high temperature history Y / N History of dirt on front radar sensor LH Y / N Front radar sensor LH high temperature history Y / N Recognition camera image malfunction history Y / N Driver monitor image malfunction history Y / N PCS cancel switch condition ON / OFF VSC OFF switch condition ON / OFF Other Differences from standard vehicle Tires / Wheels / Suspension / Other () / None Additional Customer Problem Analysis Sheet Result Proceed to NEXT Result: 1 NEXT See step 3
3. INSPECT BATTERY VOLTAGE Measure the battery voltage. Standard Voltage 11 to 14 V If the voltage is below 11 V, replace or recharge the battery before proceeding to the next step. Result Proceed to NEXT Result: 1 NEXT See step 4
4. INSPECT MILLIMETER WAVE RADAR SENSOR ASSEMBLY (BEAM AXIS MISALIGNMENT READING)* Adjust the reflector height. Refer to «ADJUSTMENT [04/2013 - ]»(ref-665556-S25139163572014102400000) Place the reflector. Refer to «ADJUSTMENT [04/2013 - ]»(ref-665556-S25139163572014102400000) Connect the Techstream to the DLC3. Turn the Techstream on. Turn the cruise control switch (ON/OFF button) on. Enter the following menus: Powertrain / Radar Cruise / Utility / Beam Axis Misalignment Reading. Check the amount of misalignment and make a note. Powertrain > Radar Cruise > Utility Tester Display Beam Axis Misalignment Reading Result Proceed to NEXT Result: 1 NEXT See step 5
5. CHECK CAN COMMUNICATION SYSTEM* Use the Techstream to check if the CAN communication system is functioning normally. Result Result Proceed to CAN communication system DTCs are not output A CAN communication system DTCs are output B Result: 2 B GO TO CAN COMMUNICATION SYSTEM. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [04/2013 - ]»(ref-665785-S15342612202014102400000) Result: 1 A See step 6
6. CHECK FOR DTCs (PRE-COLLISION 2)* Check for DTCs and note any codes that are output. Refer to «DTC CHECK/CLEAR [04/2013 - ]»(ref-665869-S07968036322014102400000) Body Electrical > Pre-Collision 2 > Trouble Codes Clear the DTCs. Refer to «DTC CHECK/CLEAR [04/2013 - ]»(ref-665869-S07968036322014102400000) Body Electrical > Pre-Collision 2 > Clear DTCs Recheck for DTCs. Try to reproduce the DTCs by duplicating the conditions indicated by the DTCs. Refer to «DTC CHECK/CLEAR [04/2013 - ]»(ref-665869-S07968036322014102400000) Body Electrical > Pre-Collision 2 > Trouble Codes Result Result Proceed to DTCs are not output A DTCs are output B DTCs are not output, and malfunction cannot be duplicated or checked C Result: 2 B GO TO DTC TABLE. Refer to «DIAGNOSTIC TROUBLE CODE TABLE [04/2013 - ]»(ref-665869-S36698318262014102400000) Result: 3 C GO TO SYMPTOM SIMULATION. Refer to «HOW TO PROCEED WITH TROUBLESHOOTING [04/2013 - ]»(ref-665529-S21853141262014102400000) Result: 1 A See step 7
7. PROBLEM SYMPTOMS TABLE HINT: Refer to Problem Symptoms Table. Refer to «PROBLEM SYMPTOMS TABLE [04/2013 - ]»(ref-665869-S11315963652014102400000) Result Result Proceed to Fault is not listed in Problem Symptoms Table A Fault is listed in Problem Symptoms Table B Result: 2 B See step 9 Result: 1 A See step 8
8. OVERALL ANALYSIS AND TROUBLESHOOTING* Terminals of ECU Refer to «TERMINALS OF ECU [04/2013 - ]»(ref-665869-S08169823952014102400000) Data List/Active Test Refer to «DATA LIST/ACTIVE TEST [04/2013 - ]»(ref-665869-S23888631342014102400000) Result Proceed to NEXT Result: 1 NEXT See step 9
9. ADJUST, REPAIR OR REPLACE NOTE: When the millimeter wave radar sensor assembly is replaced with a new one, adjustment of the radar sensor beam axis must be performed. Refer to «ADJUSTMENT [04/2013 - ]»(ref-665556-S25139163572014102400000) Result Proceed to NEXT Result: 1 NEXT See step 10
10. CONFIRMATION TEST Result Proceed to NEXT Result: 1 NEXT END

FAIL-SAFE TABLE [04/2013 - ]

HINT

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