Hệ thống treo điều khiển điện tử (ECS) được phát triển để mang đến sự thoải mái khi lái xe phù hợp và ổn định lái xe trong các điều kiện lái xe khác nhau. Một hệ thống treo được thiết kế để hỗ trợ trọng lượng xe để cải thiện thoải mái đi xe và ổn định lái xe. Nó cải thiện lực kéo bề mặt lốp xe của một chiếc xe đang được điều khiển và hấp thụ rung động cơ thể xe và tác động do tiếp xúc bề mặt. Tuy nhiên, hệ thống treo không thể đảm bảo cả sự thoải mái khi lái xe và sự ổn định lái xe vì lực giảm xóc liên tục và giảm chấn của lò xo được đưa ra trong một khung cảnh nhất định. Ví dụ, một hằng số đàn hồi thấp hơn được sử dụng cho một chuyến đi mượt mà và thoải mái hơn, nhưng điều này dẫn đến sự chuyển động lò xo tăng từ các yếu tố môi trường cũng như sự chuyển động của chính chiếc xe. Vì lý do này, độ ổn định lái của hằng số đàn hồi thấp hơn được giảm tốc độ cao và bề mặt không đồng đều. ECS giải quyết vấn đề này bằng cách giảm lực giảm chấn của hệ thống treo cho sự thoải mái khi lái xe trong điều kiện lái xe bình thường và tăng lực giảm chấn khi lái xe trên các bề mặt không đồng đều và ở tốc độ cao để ổn định lái xe. Nói ngắn gọn, ECS thay đổi không đổi độ đàn hồi, giảm chấn và áp suất mạch giảm sốc bằng nệm khí theo tốc độ lái xe và điều kiện đường để kiểm soát chiều cao vị trí của xe để cải thiện độ ổn định lái xe và thoải mái khi lái xe.
Textbook Module6 ECS (Electronic Control Suspension) Module6 ECS (Electronic Control Suspension) 6.1 O nl y LESSON Overview 145 6.1.1 Introduction 145 6.1.2 History 146 Electronic Control Suspension 147 6.3 Overview 147 Layout 148 Components 149 Control 152 lU 6.2.1 6.2.2 6.2.3 6.2.4 se 6.2 Electronic Control Air Suspension 155 na 6.3.1 Overview 155 6.3.2 Layout 156 6.3.3 Components 157 6.3.4 Control 162 Cautionary Measures for Handling Different Parts 167 Air Filling 169 Maintenance Measures by Case 171 Cautionary Measures for Lift-up (Iinitialized Vehicles) 172 Cautionary Measures for Towing 173 Fo r Ed 6.4.1 6.4.2 6.4.3 6.4.4 6.4.5 tio Maintenance (for ECAS) 167 uc a 6.4 [Learning Objective] ▪ Describe the history of ECS and different types of control ▪ Describe the system layout and list the locations, mechanisms and functions of components ▪ Create a pneumatic circuit for vehicle height control by ECAS ▪ Take necessary actions after a part change and list the cautionary measures required for maintenance Basic Chassis Technology 143 Textbook Fo r Ed uc a tio na lU se O nl y Module6 ECS (Electronic Control Suspension) 144 Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) 6.1 Overview 6.1.1 Introduction Electronic Control Suspension (ECS) was developed to provide consistent ride comfort and driving stability in various driving conditions O nl y A suspension system is designed to support vehicle weight for improved ride comfort and driving stability It improves the tire-surface traction of a vehicle being driven and absorbs vehicle body vibration and impact caused by surface contact se However, suspension systems cannot guarantee both ride comfort and driving stability as their spring constant and shock absorber damping force are given a certain setting For example, a lower spring constant is used for a smoother and more comfortable ride, but this results in increased spring movement from environmental elements as well as the movement of the vehicle itself For this reason, a lower spring constant's driving stability is reduced by high speeds and uneven surfaces Fo r Ed uc a tio na lU ECS addresses this issue by reducing a suspension's damping force for ride comfort in normal driving conditions and increasing the damping force when driving on uneven surfaces and at high speeds for driving stability In short, ECS varies spring constant, shock absorber damping force and air spring circuit pressure according to driving speeds and road conditions to control vehicle height/position for improved driving stability and ride comfort Conventional Suspension System ECS (Electric Control Suspension) Cannot provide both ride comfort and driving stability Controlled to suit different driving conditions for both ride comfort and driving stability Basic Chassis Technology 145 Module6 ECS (Electronic Control Suspension) 6.1.2 Textbook History There are two types of ECS: Electronic Control Suspension and Electronic Control Air Suspension ECS controls damping force and is generally found in mid-size passenger vehicles By adjusting the oil flow inside the shock absorbers, ECU controls the shock absorber damping force according to vehicle movement to produce vehicle movement that is optimum for given driving conditions Fo r Ed uc a tio na lU se O nl y ECAS controls damping force and vehicle height, and is generally found in luxury passenger vehicles Its components include a variable damper, for damping force control, and a length-adjustable air spring The air spring ensures driving stability by keeping the position of an accelerating, braking or cornering vehicle horizontal High-frequency vibrations that coil springs cannot absorb are absorbed by air springs, which results in ride comfort As such, vehicle-height-controlling suspension systems are ideal as they provide both ride comfort and driving stability 146 Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) 6.2 Electronic Control Suspension 6.2.1 Overview O nl y ECS controls a vehicle's damping force in real-time according to the driver's settings and driving conditions for optimum ride comfort and enhanced driving stability The damping force of the shock absorbers installed on a vehicle's four wheels are adjusted to an optimum level by ECU to keep the vehicle as level with the ground as possible at all times Fo r Ed uc a tio na lU se In older-model vehicles, damping force was controlled in three stages; in late-model vehicles, non-staged precision control of damping force is achieved through variable dampers Basic Chassis Technology 147 Module6 ECS (Electronic Control Suspension) Layout uc a tio na lU se O nl y 6.2.2 Textbook Fo r Ed Damping-force-controlling ECS continuously adjust each wheel's damping force through continuously variable dampers to produce optimum vehicle movement It receives signals from the body G sensor (detects vehicle movement), wheel G sensor, steering angle sensor (detects the driver's intentions), speed sensor and TPS to identify the driving conditions Damping-force-controlling ECS components include an ECS mode switch, for enabling damping force control mode, and ECS lamp, which indicates system troubles and ECS mode 148 Basic Chassis Technology Textbook 6.2.3 Module6 ECS (Electronic Control Suspension) Components 1) Continuously Variable Damper Functions and Roles lU se O nl y Made up of an integrated shock absorber and solenoid valve, a continuously variable damper is installed on each of a vehicle's four wheels Solenoid valve control allows damping force (force that tries to stop spring movement against the shock absorber) to be continuously controlled na Mechanism tio ECS ECU controls the damping force variable solenoid valve according to driving conditions Current control moves the spool valve inside the solenoid valve to change the flow and continuously switch the damping force of the continuously variable damper Fo r Ed uc a An electrical current between 0.3-1.3 A is needed for the external solenoid valve Current adjustment to 0.3A moves the spool valve up and constricts the orifice, slowing down oil flow and increasing damping force; this "hardens" the ride feel (hard mode) Conversely, current adjustment to 1.3A moves the spool valve down and expands the orifice, speeding up oil flow and decreasing damping force; this "softens" the ride feel (soft mode) Basic Chassis Technology 149 Module6 ECS (Electronic Control Suspension) Textbook 2) Body G Sensor se O nl y The body G sensor measures vehicle acceleration at the top and bottom to detect upper/lower vehicle body movement It provides the main signals used in anti-bounce, anti-pitch and anti-roll control Detection of movement on a flat surface requires at least three sensors; two G sensors are installed in the engine room and another on the trunk left panel If the body acceleration sensors are mounted at just the front and rear, surface changes are harder to detect, which leads to a reduction in vehicle control The sensors must be installed with the arrow pointing down toward the surface lU 3) Wheel G Sensor tio 4) SAS (Steering Angle Sensor) na Installed under the continuously variable damper of the front wheels, the wheel G sensor detects tire operation and continuously variable damper speed in harsh conditions mode It can detect the surface quality of unpaved roads and the rough conditions of uneven surfaces Compared to conventional versions, the damper is precisely controlled to improve ride comfort as the vehicle passes over uneven road surfaces uc a The steering angle sensor detects steering speed and angle to detect vehicle body roll It provides the input signals required for anti-roll control This sensor is installed inside the MDPS assembly and receives signals through CAN communication with MDPS 5) WSS (Wheel Speed Sensor) Fo r Ed The wheel speed sensor detects wheel speed to provide the input signals required for handling, anti-squat and high-speed stability control It uses a hall element and is installed on the tone wheel, and receives signals through CAN communication with ECS/ABS Wheel G Sensor 150 SAS (Steering Angle Sensor) WSS (Wheel Speed Sensor) Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) 6) ECS Mode Switch O nl y Figure 6-1 ECS Switch The ECS mode switch (self-return-type) is used by the driver to switch between sport mode and normal mode to suit driving conditions A single press enables sport mode and another single press enables auto mode se Sport mode puts CDC in "hard mode" to improve driving stability at the expense of ride comfort for driving through multiple bends and sporty driving lU 7) ECS ECU na ECS ECU is installed on the right of the center of the cowl crossbar With vehicle driving/position data received from various sensors, ECS ECU performs real-time solenoid valve control for adjustment of the damping force of the variable dampers installed a vehicle's four wheels Fo r Ed uc a tio ESC ECU operation is controlled by the actuator relay located at the center of the dash panel Upon activation, the actuator relay supplies currents to the damping force variable solenoid vagve through the ECU's internal circuit If engine RPM falls below 500 while driving, ECU stops actuator relay operation 8) ECS Lamp Located on the cluster, the ECS indicator switches on when sport mode is selected, blinks when ECS is faulty and switches off in normal mode Contacts are controlled according to ECU switch signals or in the event of ECU trouble Figure 6-2 ECS Lamp Basic Chassis Technology 151 Module6 ECS (Electronic Control Suspension) 6.2.4 Textbook Control na lU se O nl y 1) Input & Output Elements Ed 2) System Control uc a tio Power-supply to ECS ECU triggers ECU to inspect components and prepare for operation The body G sensor and wheel G sensor detect vehicle movement and send data to ECU The driver's intentions are detected through the ECS mode switch, vehicle speed, throttle position sensor, brakes and steering angle sensor; after required damping force control is calculated, the damping force variable solenoid is controlled When sport mode is enabled, the ECS indicator switches on In the event of system trouble, the ECS warning lamp blinks and communication takes place with external diagnostic equipment for trouble diagnosis Fo r Item Ride control logic (pitch, bounce) Description Input Element Top/bottom vibration suppression when driving on an inflected surface Body G Sensor (3EA) Control Wheel G sensor (2EA) ECS mode switch Road Detection → Skyhook Control Left/right vibration suppression during turns Steering Angle Sensor ECS mode switch Anti-roll control logic 152 Basic Chassis Technology Module6 ECS (Electronic Control Suspension) Textbook G Sensor O nl y An acceleration sensor is installed on FL, FR and RL for measuring the vehicle body's vertical acceleration and sending signals to ECS ECU Based on incoming vehicle body vertical acceleration signals, ECU calculates the vehicle's top/bottom, pitch, roll and vibration speed Based on these speed elements, damping force is controlled to suppress vehicle body vibration Pressure Sensor uc a tio na lU se Installed on the valve block, a pressure sensor detects pressure in the system When ECS is not operating, it monitors system pressure for the reservoir tank; when ECS is operating, it monitors system circuit pressure for air spring operation ECS Mode Switch Ed Four vehicle height sensors are installed on the vehicle body and lower arm to detect the height of the vehicle when moving The vehicle body's top/bottom acceleration is sent to ECS ECU as signals from the sensor rod for use in vehicle height control Fo r • Vehicle Height Control Switch The driver can change the vehicle height by selecting high mode or normal mode Low mode is not switch-selectable and is enabled automatically when the vehicle maintains a speed of 120km/h or higher for more than 10 seconds • Damping Force Control Switch The driver can adjust damping force by selecting sport mode or auto mode 160 Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) ESC ECU ESC ECU is located in the LH trim in the trunk and receives driving conditions/position signals from sensors and controls the vehicle height and damping force Vehicle height is controlled automatically according to vehicle speed; it can be controlled using the vehicle height control button also ECS Lamp Fo r Ed uc a tio na lU se O nl y The ECS indicator is located on the cluster The "High" lamp is switched on when high mode is enabled for vehicle height control The "Sport" lamp is switched on when sport mode is enabled for damping force control Basic Chassis Technology 161 Module6 ECS (Electronic Control Suspension) 6.3.4 Textbook Control tio na lU se O nl y 1) Input & Output Elements uc a ECS ECU detects vehicle movement through the vehicle height sensor, G sensor and pressure sensor, and recognizes the driver's intentions through the ECS mode switch Calculations for vehicle height and damping force control are made based on data received from ECM, ABS/ESC and MDPS Air flow is controlled through the solenoid valve, exhaust valve, reversing valve and compressor relay to increase or decrease vehicle height Damping force is made hard or soft through the variable damper valve for ride comfort and driving stability ● Ed 2) Vehicle Level Control Overview Fo r Vehicle height can be controlled while driving or stationary manually or automatically The driver the can manually control the vehicle height switch to select one of two levels (normal/off-road) Auto mode lets ECU adjust vehicle height to level ideal for given driving conditions Adjustable levels include Normal (design height), Highway (low) and Off-road (high) Pneumatic control occurs as shown in the diagram below for height height control when certain conditions are met 162 Basic Chassis Technology Module6 ECS (Electronic Control Suspension) se O nl y Textbook lU Vehicle control is based on vehicle height sensor signals (4EA), pressure sensor signals, wake-up signals (vehicle IGN signals) and CAN signals Level Operating Modes tio ● na Reservoir pressure is checked after a set time when vehicle height control is finished In case of a pneumatic pressure shortage, a refill takes place only when traveling at a certain speed for the following control The reason a certain speed is required is because noise and vibration are likely to occur from compressor activation Vehicle control takes place in the various operating modes of ECU uc a • Sleep state Ed Sleep mode reduces ECU's power consumption Level control is disabled in sleep mode Sleep mode is exited when ECU detects a ECU wake-up pin or when IGN is switched on After IGN switch-off, ECU enters sleep mode after a set delay time A vehicle left in sleep mode for a prolonged time wakes up ECU every two, five and ten hours (adjustable) for normal vehicle height maintenance • Wakening state Fo r The period between IGN switch-off and sleep mode entry is referred to as wakening mode In this mode, vehicle height cannot be manually controlled using HMI and only automatic vehicle height control takes place • IGNITION state ECU enters ignition mode if the IGN switched on but the engine fails to start Level control is not available in this mode • Standstill state ECU converts to standstill mode if the IGN switched on and the engine starts Level change the user desires can take place in this mode • Drive state ECU enters drive mode when a certain speed threshold (adjustable) is reached In this mode, both manual and automatic level change can take place Manual level change requires the vehicle speed to be under 70; if higher than 70, vehicle height is returned to normal automatically Vehicle height is automatically lowered when vehicle speed of 120 or higher is maintained for 10 seconds, before returning to normal when vehicle speed is maintained at 80 or lower for seconds Basic Chassis Technology 163 Module6 ECS (Electronic Control Suspension) Textbook O nl y • CarLift state se When a vehicle is placed on a lift for maintenance, the space between its wheels and body widens The vehicle recognizes this as increased vehicle height and the automatic vehicle height calibration function can lower the vehicle body, resulting in air discharge from air springs To prevent this issue, put the vehicle in the "car lift state" to prevent unnecessary vehicle height control Car list mode is changed to ignition mode if ignition is turned on, and changes to drive mode if vehicle speed increases ● lU 3) Damping Control Overview ● tio na The body of a moving vehicle vibrates constantly due to contact with (uneven) road surfaces, possibly causing the driver discomfort Damping control prevents this issue through continuous damping force control through variable dampers for optimum ride comfort and driving stability Skyhook Fo r Ed uc a Skyhook control is one of the most effective algorithms for vehicle suspension damping control From virtual coordinates located in the space above a vehicle, the vehicle body's up/down vibration is detected and skyhook dampers' damping force is increased appropriately to reduce vehicle body vibration ● Ride comfort control • Anti-squat: Changes all CDC dampers from soft to hard during sudden acceleration, before gradually reverting to soft mode (check engine torque) • Anti-Dive: Changes all CDC Dampers from Soft→Hard during sudden braking, and slowly restores Soft Mode (check brake pressure) • Anti-Roll: Changes all CDC Dampers from Soft→Hard during hard turn, and slowly restores Soft Mode (check Latitudinal-G and steering angle) 164 Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) • Anti-Dive: Changes all CDC Dampers from Soft→Hard during sudden braking, and slowly restores Soft Mode (check brake • Bump mode: Changes all CDC Dampers from Soft→Hardwhen a bump is driven over, before O nl y gradually reverting to soft mode (check vehicle height) se 4) Air Supply System Control lU A pneumatic circuit is made up of a compressor, valve block, reservoir tank and four air springs Air flow in the pneumatic circuit is controlled for vehicle height control, air spring air discharge and pressure measurement/control Fo r Ed uc a tio na An open-loop system was used in the past, which produced limited energy efficiency from slow vehicle height control resulting from external air exchange during forced exhaust On the other hand, the latest closed-loop systems achieve fast vehicle height control and high energy efficiency Compressor Air Spring Valve Air Dryer Pressure Sensor Throttle / Check Valve 10 Relief Pressure Valve / Reversing Valves 11 Air Filling Valve Reservoir Tank 12 Suction Hose with Air Filter Environment Valve 13 Exhaust Hose Basic Chassis Technology 165 Module6 ECS (Electronic Control Suspension) Textbook Decrease Ground Clearance When vehicle height is increased, the motor in the compressor starts up to supply air in the reservoir to the valve block through the reversing valve Solenoid valves in the valve block then supply air to the air springs to lift the vehicle body up Air supplied to the air springs from the reservoir tank are returned to the reservoir tank through the air dryer, resulting in increased reservoir tank pressure Air Refill Air Exhaust na lU se O nl y Increase Ground Clearance uc a tio When the system is short of air, external air is sucked in through the external air filter for pressure supplementation Excess pressure in the system is removed by releasing air into the atmosphere through the external air filter Air is released into the atmosphere through the reversing valve, environment valve and air filter Fo r Ed Air-Filling Air is filled through the air injection valve when more air is required in the ECS system Air sucked in through the reservoir tank is supplied to the four air springs by the compressor motor 166 Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) 6.4 Maintenance (for ECAS) 6.4.1 Cautionary Measures for Handling Different Parts O nl y 1) FW Air Strut ▪ To assemble the FW strut, assemble the lower part first and raise the lower arm before assembling the upper part (potential buckling if done in the reverse order) ▪ Do not hold the gaiter or cable when loading or moving the FW strut (potential bellows damage from exterior defect/interior interference or CDC malfunction from cable disconnection) lU Do not hold when loading/moving se ▪ Check for air inside the springs and any distortion (potential damage from a distorted bellows) uc a 2) Rear Air Spring tio na CAUTION ▪ Do not pull on rear air springs during maintenance ▪ Check the state of the upper pad and bearing installation when assembling rear air springs Ed ▪ Do not lower the vehicle onto the floor and fill air after changing air springs (air spring buckling highly likely) → Fill air with the vehicle lifted up, i.e with all wheels fully rebound Fo r → Replace springs with new ones if buckling occurs Basic Chassis Technology 167 Module6 ECS (Electronic Control Suspension) Textbook 3) Solenoid Valve ▪ Check and ensure that marking colors on the connector match when assembling the solenoid valve and tube to prevent faulty assembly ▪ Remove contaminant-blocking plug right before assembly O nl y ▪ Prevent falls (leakage through fine cracks in the plastic body) ● Cautionary Measure for Air Tube Maintenance se 4) Air Tube lU • Keep tube exterior and ends round to prevent o-ring damage during tube insertion • Avoid excessive force during tube insertion to prevent a block from crumpling to keep air tube in place) tio • Keep tubes in storage from bending na • Insert up to the marked area and pull to check assembly soundness (sufficient pressure is required ● Ed uc a • Do not hold/carry the compressor by wiring Air Tube Disassembly • Remove the air connector from the tube by turning it counter clockwise (air connector rotates freely Fo r after disconnection) • Push the tube inside to remove the grip ring and then separate the connector from the tube • If the end of the tube is damaged, use a cutter to cut about 3–4 mm off the tube end and then reconnect the tube with a new connector ● Air Tube Re-assembly • Check spec torque (5–6 N.m) when connecting with a new connector • Do not remove the dust cover cap until the tube assembly is completed • Check the damage state at the tube end (prevent O-Ring damage), and if there is no damage, slowly insert the tube up to the marked section • Pull on the tube 2–3 times to ensure proper connection • Check with soapy water for air leak after filling the air 168 Basic Chassis Technology Textbook 6.4.2 Module6 ECS (Electronic Control Suspension) Air Filling 1) Purpose After exchanging air suspension's air pressure related components (air spring, compressor, etc.), use the air filler to fill moisture and impurity removed high quality air O nl y Using a compressor to fill air can result in dryer overload, which can result in air containing moisture entering the system As moisture in the system can cause malfunction or compressor damage from freezing in the wintertime, always use a air-filling device to fill air into the system 2) Before Starting Work ▪ Check the relative locations of the rear air springs and vehicle body before filling air (see diagram below) uc a tio na lU se Buckling, damage or interference can occur if springs are not in place properly If required, remove and check the springs for soundness ▪ Ensure that all wheels are fully rebound before air-filling Ensure that the vehicle is lifted up on a lift for air-filling to prevent air spring buckling Fo r Ed ▪ Air-filling and discharge of the ECS system can only be done using diagnostic equipment In other words, no other methods must be used for air-filling and discharge Use diagnostic equipment to remove contaminants in the air and fill air with the pressure increased to 12bar (set to 12bar at factory release; no adjustment required) Basic Chassis Technology 169 Module6 ECS (Electronic Control Suspension) Textbook 3) Working Order Connect the inlet coupler on to the inlet connection part Connect the factory air coupler on to the air inlet part in the back (check that inlet air pressure is 5bar) The device activates automatically when the connection is made, and the inlet air pressure elevates to 12bar (takes about minute) Wait about 10 minutes after charging and then start the task (time required for removing air moisture) Connect the inlet coupler to the vehicle's air inlet nozzle Pull back and forth to check the connection Connect the diagnosis device and select ECS Air Fill option O nl y → Air Inlet Nozzle connection position: Above the front left wheel house Ed uc a tio na lU se Disconnect the diagnosis device and the air coupler when the air filling is complete 4) Precautions Fo r ▪ Pressurized air is released Do not point the nozzle at people ▪ Check connector soundness before working ▪ Replace the filter every two years 170 Basic Chassis Technology Textbook 6.4.3 Module6 ECS (Electronic Control Suspension) Maintenance Measures by Case 1) Replacing FW/RW air springs or pneumatic components (solenoid block, air tank, etc) Exhaust: Connect the diagnostic equipment and select "Air Spring Exhaust/Reservoir Exhaust" to discharge air from the required component O nl y Part change: Change the required part and check the pneumatic line connection (prevent tube disconnection during air-filling from faulty insertion) Air Filling: With the vehicle lifted up and wheels removed, connect the air-filling device to the vehicle's air-filling port se If the entire system requires air-filling, connect the diagnostic equipment and select "System Filling," which has two available mode • Standard: 7bar for FW, 5.5bar for RW and 10 bar for air tank (filled in sequence) • Custom: Lets you set a pressure for each component and fill the FW, RW and air tank in sequence lU For partial air-filling, select "Air Spring Filling," set the appropriate pressure (7bar for FW, 5.5bar for RW) and fill air tio na Vehicle height sensor calibration: Lower the lift when air-filling is finished, visually inspect the vehicle height, move the vehicle to the station (alignment equipment) and perform vehicle height sensor calibration Enter the vehicle height (FW, RW) and use the calibration data to adjust to normal vehicle height uc a The vehicle will be lowered and raised again automatically during calibration, so stand by until it comes to a stop If the measured height exceeds ±40mm, calibration cannot be performed; inspect suspension system components and vehicle height sensor before another calibration Keep the vehicle height control lock in place if calibration is not completed normally Ed 2) Installing a New ECS ECU Fo r ECU change: Remove and replace ECU in key-off state Variant coding: Connect diagnostic equipment and perform variant coding for ECU initialization and specifications setting (variant coding cannot be performed while idle) ECU reset: Select ECU Reset on the diagnostic equipment menu Diagnostic equipment is disconnected at reset and requires reconnection Vehicle height sensor calibration: Lower the lift when air-filling is finished, visually inspect the vehicle height, move the vehicle to the station (alignment equipment) and perform vehicle height sensor calibration Basic Chassis Technology 171 Module6 ECS (Electronic Control Suspension) 6.4.4 Textbook Cautionary Measures for Lift-up (Iinitialized Vehicles) When air suspension part replacement is required, place the vehicle on a lift, turn off the engine and raise the lift after one minute before disabling the vehicle height calibration function Fo r Ed uc a tio na lU se O nl y Before getting off the lift after work has finished, press HIGH on the ECS switch to increase the vehicle height to prevent the bottom of the vehicle hitting a part of the lift 172 Basic Chassis Technology Textbook 6.4.5 Module6 ECS (Electronic Control Suspension) Cautionary Measures for Towing Fo r Ed uc a tio na lU se O nl y Tow the vehicle to a service center if air springs get damaged and fall off or if air spring damage is suspected The angle at which the vehicle can be towed depends on its state Basic Chassis Technology 173 Textbook Fo r Ed uc a tio na lU se O nl y Module6 ECS (Electronic Control Suspension) 174 Basic Chassis Technology ... y Module6 ECS (Electronic Control Suspension) 144 Basic Chassis Technology Textbook Module6 ECS (Electronic Control Suspension) 6. 1 Overview 6. 1.1 Introduction Electronic Control Suspension (ECS) ... Technology 145 Module6 ECS (Electronic Control Suspension) 6. 1.2 Textbook History There are two types of ECS: Electronic Control Suspension and Electronic Control Air Suspension ECS controls damping... force control Basic Chassis Technology 153 Textbook Fo r Ed uc a tio na lU se O nl y Module6 ECS (Electronic Control Suspension) 154 Basic Chassis Technology Textbook Module6 ECS (Electronic Control