Published by Hyundai Motor company, september 2005 Centennial Semi-Active ECS (Electronic Controlled Suspension)

2 RIDE & HANDLING CHARACTERISTICS Sporty Limousine Adaptive ECS Semi-Active ECS Conventional Handling & Road Holding Ride Comfort GOOD POOR

3 GENERAL This Continuous Variable Semi-Active suspension system with a proportional actuator, based on the reverse damping force type damper to achieve smoother ride comfort. Semi-Active Suspension is based on the sky-hook theory. This theory has been established by Dr. Karnopp in He considered, if the damper is hooked to the absolute axis, vibration of the mass will be most effectively absorbed. And absolute axis looks like sky, so he named this theory sky hook theory. But, in case of applying this theory to the vehicle, there is no reality. Instead of using sky hook damper, he considered to use variable damper as a system with the same effect. This idea is so called sky-hook semi-active system. The basic signals for detecting the body up-down movement are acceleration sensors which are mounted on the sprung mass. In addition, the information from the steering sensor, TPS, brake switch, vehicle speed sensor are used for the vehicle maneuver. According to the information from the sensors, ECS control module decides the damping force of each shockabsorber by managing the applying current to the proportional solenoid valve which is attached on the shockabsorber. ECS system has a ECS select switch. So drivers can choose the riding feeling between the normal mode or the sport mode.

4 [Practical use] Sprung weight Sprung weight SKY HOOK DAMPER [Ideal case] (Wheel) (Body)

5 Sky-Hook control by using Reverse Damper Damper Velocity HardSoft Hard Body Movement Down (X 1 < 0 )Up (X 1 > 0 ) Rebound X1X1 -X0X0 > 0 Compression < 0 Reverse Damper H/ S mode (0.3 ~ 0.8 A) S/H mode (0.8 ~ 1.3 A) X1X1 -X0X0 SKY HOOK DAMPER

6 Example of Sky-Hook control SKY HOOK DAMPER

7 Jounce Damping Rebound Damping Actuator position Rebound Damping Jounce Damping Actuator position H/HH/S (Reverse Type) Advantage of reverse type damper SKY HOOK DAMPER

8 * Piston speed: 0.3m/s H/S 2 4 S/H S/S Damping force [kN] 2 0 Current [A] Reverse Damping Characteristics Damping force characteristics SKY HOOK DAMPER

9 Damping force characteristics As the damping force characteristics figured in this schematic, the shock absorber has the reverse damping force type. The input current of the proportional solenoid is between 0.3 A of H/S position and 1.3 A of S/H position. The current of S/S position is 0.8 A. When the actuator fail with 0 A condition, the position turns to H/S position. When the current is going down from 0.8 A of S/S position, the rebound side damping force increase the orifice characteristic and make the blow off point higher. When the current is going up form 0.8 A, the jouncing side damping force increase the orifice characteristic and make the blow off point higher. SKY HOOK DAMPER

10 Actuator: Proportional solenoid valve Control step: continuous Response time: 20 ~ 30ms (S/H H/S) Current control: 0.3 ~ 1.3A Max. SYSTEM PERFORMANCE Semi-active control using vertical G sensor (Pitching and Bouncing Control) Variable damping control using existing sensors (Rolling, Diving and Squatting Control) BODY CONTROL Shock absorber: Reverse damping force type DAMPING FORCE CONTROL ACTUATOR

11 SHOCK ABSORBER Design concept Gas pressure Reservoir oil level Variation of oil level while operation

12 Rebound Compression Variable Control Valve Proportional Solenoid Oil flow ECS SHOCK ABSORBER

13 Rebound Compression Oil flow ECS SHOCK ABSORBER

14 Rebound main valve Compression main valve Proportional solenoid Pilot valve spool Rebound Compression Rebound Compression Current controlled proportional solenoid ECS SHOCK ABSORBER

15 Current controlled proportional solenoid In the case of rebound process, the procedure to change damping force hard is ; -reduce the current of solenoid actuator -then the pilot spool moves to right side and choke the area of control port, -so that the damping force of orifice control increases and the room pressure behind the main valve is increased, As the result, the damping force turn to hard due to increase of opening pressure of main valve. ECS SHOCK ABSORBER

16 Current controlled proportional solenoid The procedure to change damping force soft is ; -increase the current of solenoid actuator -then the pilot spool moves to left side and open the area of control port, -oil flows both through the orifice of the rebound side main valve and the control port of the pilot spool, -so that the damping force of orifice control reduce, -and same time the room pressure behind the main valve decrease due to the pressure drop of the main valve orifice, -then the blow off point of main valve moves to lower side, As the result, the damping force turn to soft.In the case of jouncing process, if you want to make it hard, the current should be increased, if you want to make it soft, the current should be decreased. ECS SHOCK ABSORBER

17 (0.3 A 1.3 A) CONTROL CURRENT 0.3 A : Rebound Hard / Compression Soft 0.8 A : Rebound Soft / Compression Soft MAX. 50ms (H/SS/H,S/HH/S)RESPONSE TIME 1.3 A : Rebound Soft / Compression Hard COIL RESISTANCE 4.1 ±0.3 (20 ) ITEMSSPECIFICATION Specification ECS SHOCK ABSORBER

18 CONTROL LOGIC

19 Pitching and bouncing movements are controlled in relate to the vertical acceleration sensor signal. Roll, dive, squat movements are controlled in relate to the speed sensor, the steering sensor and brake switch and throttle position sensor. The fundamental concept of this system logic is as follows - Calculate the absolute unsprung speed by integrating the output of acceleration sensor on the unsprung. - Then decide target damping force depend upon the proportional rate of the absolute speed, and control the actuator output accordingly. Body control CONTROL LOGIC

20 a) Road judgement control This purpose is improvement of control effect and preventive of ride comfort go worse. Road judgement condition use acceleration sensor and ECU change the parameters use this result. Judgement result is decided by acceleration sensor signal of FR and FL. There is no priority between FR and FL. * Sensor : G Sensor (FR,FL) Ride control Road Condition G LevelFrequencyOthers Bad 2Over 0.19GOver 5 Hz- Long WaveOver 0.17GFrom 1 to 3 Hz When single wave judgement, Continue 4 seconds Apart bumpOver 0.29GFrom 1 to 3 HzUnder 51 km/h Single WaveOver.17GFrom 1 to 3 Hz- Bad 1Over 0.15GOver 5 Hz- NormalOthers(initial) CONTROL LOGIC

21 b) Anti–bounce feed back Control This purpose is control of bounce. Add front and rear body velocities, ECU control the damping forces in proportion to this result. Ride control Item Sensor Logic Contents Acceleration Sensor FR, FL, RR Integration Body Velocity From Acceleration (FR Body Velocity) + (FL Body Velocity) + (RR Body Velocity) + (RL Body Velocity) CONTROL LOGIC

22 Item Sensor Logic Contents Acceleration Sensor FR, FL, RR Integration Body Velocity From Acceleration (FR Body Velocity) - (RR Body Velocity) (FL Body Velocity) - (RL Body Velocity) c) Anti–pitch feed back Control This purpose is control of pitching. Subtract front and rear body velocities, ECU control the damping forces in proportion to this result. Ride control CONTROL LOGIC

23 d) Anti–roll feed back Control This purpose is control of roll. This purpose is control of roll.Subtract right and left body velocities, ECU control the damping forces in proportion to this result. Ride control Item Sensor Logic Contents Acceleration Sensor FR, FL, RR Integration Body Velocity From Acceleration (FR Body Velocity) - (FL Body Velocity) (RR Body Velocity) - (RL Body Velocity) CONTROL LOGIC

24 a) Anti–roll feed forward Control This purpose is control of roll. Use steering and speed sensor, ECU control the damping forces use these sensors outputs. * Damping control: Rebound Hard (H/S) Handling Item Sensor Logic Contents Steering sensor, vehicle speed sensor Difference lateral acceleration CONTROL LOGIC

25 b) Anti–dive Control This purpose is control of dive. Use brake switch and speed sensor, ECU control the damping forces use these sensors outputs. * Damping control: Front Compession Hard (S/H), Rear Rebound Hard (H/S) Handling Item Sensor Logic Contents Brake switch, vehicle speed sensor Differential vehicle speed CONTROL LOGIC

26 c) Anti–squat Control This purpose is control of squat. Throttle position sensor output is more than standard, ECU control the damping forces front:hard/rebound, rear:soft/rebound. And it finish after a constant time pass. * Damping control: Front Rebound Hard (H/S), Rear Compression Hard (S/H) Handling Item Sensor Logic Contents Throttle position sensor, vehicle speed sensor Throttle angle and time (TPS > 56%) CONTROL LOGIC

27 d) High speed stability This purpose is control of high speed stability. Use speed sensor, ECU control the damping forces use these sensors outputs. Handling Item Sensor Logic Contents Vehicle speed sensor Vehicle speed CONTROL LOGIC

28 SYSTEM CONSTRUCTION ACTUATOR (FR) ACTUATOR (FL) ACTUATOR (RL) ACTUATOR (RR) G-SENSOR (RR) G-SENSOR (FR) G-SENSOR (FL) STEERING SENSOR ECSCM

29 CONTROL MODULE [Location: Rear right of the trunk][Control module]

30 CONTROL MODULE Block diagram

31 SYSTEM SCHEMATIC

32 INPUTS & OUTPUTS

33 Alternator L terminal Application ECS control module detects charging voltage by alternator L signal. If the charging voltage is under 8.5 voltage or over 16.5 voltage, actuator relay is off and ECS stops. Specification - Output Voltage at Engine Stop : 5V Max - Output Voltage at Engine Run : 10V Min ECS control module power supply B+ (15A, ECS solenoid relay power): if blown out C2124(Actuator relay) IG 2 (15A, ECSCM & Cluster power): if blown out Communication failure INPUTS

34 [Low voltage][Normal] Alternator L terminal INPUTS

35 ECS mode switch (Sport/Normal switch) Specification - Switch type: Normal open(Self return) - Switch on (SPORT): 0.25 V or less - Switch off (NORMAL): 4.5 V or more 0V 5V ON OFF SPORT/ NORMAL SWITCH ECSCM 5 V B4 INPUTS

36 Brake switch Application Input signal for anti-dive control Specification - Steady state characteristic : Normal open (Close at putting on the brake) - Voltage drop : 0.25V MAX (at 0.12A) DTC : No code OFF (12V) ON (0V) B3 INPUTS

37 Vehicle speed sensor Specification - Revolution : 637 rpm at 60km/h - Pulse/1 revolution : 4 Pulse/ 1 revolution - Voltage drop : 1.5V Max at 1.5mA - Output voltage: 0V, 5V - Chattering : 1 ms Max - Duty ratio : 50±20% Usage Input signal for anti-dive, anti-roll, high speed control INPUTS

38 OUTPUT SIGNAL 1HZ 5V 0V 50% 4 times on/off at 1 turning Vehicle speed sensor [Sensor circuit and sensor output characteristics] Hall Element ECSCM Output 5V IG B6 INPUTS

39 Steering sensor Specification - Sensor type : Photo interrupt type - Sensor output type : Open Collector Type - Output pulse quantity :45pulse (Pulse cycle 8°) - Duty ratio : 50±10% - Phase difference of outputs : 2.0 ±0.6° - Supply voltage :IGN1(8~16V) - Output voltage :1.3V OL2.0V, 3.3V OH4.0V -Maximum rotational velocity : 1,500°/s Usage : Input signal for anti-roll control INPUTS

40 ST 1 ST N ST 2 Slit plate Hole Application - Location: Inside steering wheel - Calculate the steering amount and direction - 3 Input Signals (ST 1, ST 2, ST N) - ST N detects the neutral position of steering wheel Steering sensor ECSCM 5V IG 12V Sensor output (ST1) INPUTS

41 ST 1 ST 2 L (1.5V) H (3.5V) L (1.5V) H (3.5V) CURRENT H L TURNING RIGHT H L L ST 1 ST 2 L (1.5V) H (3.5V) L (1.5V) H (3.5V) Steering sensor output (while turning right) INPUTS

42 Steering sensor output (while turning left) CURRENT H L TURNING LEFT H L H ST 1 ST 2 L (1.5V) H (3.5V) L (1.5V) H (3.5V) ST 1 ST 2 L (1.5V) H (3.5V) L (1.5V) H (3.5V) INPUTS

43 Steering sensor output (when the sensor connector is open) INPUTS

44 Throttle position sensor Specification - Output signal type : PWM output - Output signal duty : 5%(angle 0°) ~ 91%(angle 90°) - PWM frequency : 100Hz Usage : Anti-squat control [ Fully closed ] [ Fully open ] 11% 0V 12V 89% 80% 20% INPUTS

45 Throttle position sensor (output signal) [ Fully closed ] [ Fully open ] INPUTS

46 Output voltage (v) Throttle angle ( ) Throttle position sensor [Sensor circuit and sensor output characteristics] Sensor output TPSECM Power (5V) ECSCM B5 PWM Ground INPUTS

47 Acceleration sensor (G-sensor) Application: Main signal for driving feeling (3EA) Specification - Input Voltage : 5V±0.25V - Output Voltage : 0.55 ~ 4.45V - Nominal Sensitivity : 2.0V/g - Range : +1g ~ ­1g - Operating Temperature :­40 ~ +125 Sensor connector Sensor location (FR sensor, FL sensor, Rear sensor) INPUTS

48 Acceleration sensor Upper electrod e Lower electrode Space Moving Mass [Sensor IC construction] INPUTS

49 Acceleration sensor (G-sensor) [G-Sensor output] 4.45 [V] [G] [Sensor circuit and sensor output characteristics] Power Output 5V Ground G SENSOR ECSCM [Sensor circuit] B12 B7 B25 B8B9 INPUTS

50 Acceleration sensor (output signal) [Current data & sensor output at plane surface] 2.6 V [Acceleration sensor data: 0G][Output voltage] INPUTS

51 Acceleration sensor (output signal) [Current data & sensor output when the sensor has around 45º] 2.2 V [Acceleration sensor data: G][Output voltage] INPUTS

52 Acceleration sensor (output signal) [Current data & sensor output when the sensor has around 90º] 0.6 V [Acceleration sensor data: around - 1G][Output voltage] INPUTS

53 Acceleration sensor (output signal) [Current data & DTC when the sensor connector is open] [Acceleration sensor data: around - 1G][DTC] RR Acceleration Sensor INPUTS

54 Actuator relay Application Actuator relay is activated by ECS control module and supplies power to the proportional solenoid. Specification - Consumption Power : 1.8W (at 12 V) - Operating Temperature : ­40 ~ Control Current : 150 mA Functions - ECU ground control - While ECS control: 0V - Out of ECS control: 12V (C1107,1108,1101,2124,2212,2216,2220,2224) A1 A7 ECSCM B+ B18 OUTPUTS

55 Actuator relay (Current data when the relay is off) Actuator relay OUTPUTS

56 ECS lamp IG ECS lamp ECU Diagnostic trouble description - Type : LED - Consumption Power : Max 25mA (at 12 V) Application ECS lamp comes on when sport mode is selected or when there is a failure on the system. Lamp operation - Normal: OFF - Sport: ON - Failure: Flashing OUTPUTS

57 ECS lamp ECS Control Mode & Lamp Control Specification - While running normal, the lamp is turned on/off by switch. But the lamp is on in 3 seconds after control module started. a) Select Sport : ECS Lamp ON b) Select normal : ECS Lamp OFF ECS lamp On/Off condition Sport/Normal OFF SW ON Semi Active Normal Mode Sport ECS ON Lamp OFF OUTPUTS

58 ECS lamp on ECS switch on ECS lamp off ECS switch off ECS lamp On/Off condition OUTPUTS

59 ECS lamp Detecting troubles -If some trouble is detected, a diagnosis number coping with the trouble is recorded. AT the same time Sport lamp goes on and off. If a trouble is detected, the lamp starts going on and off. Detection 500ms Point of trouble Lamp SPORT 500ms Detecting troubles - Sport lamp turns on while HI-SCAN communicate. Lamp on timing for troubles Sport lamp turn on while Hi-scan communication Communication Finish ECS ON Lamp OFF Communication Start OUTPUTS

60 Solenoid valve (Proportional type) [Rear solenoid] [Front solenoid] OUTPUTS

61 Solenoid valve (Proportional type) Application: Main signal for driving feeling Specification - Output current range : 0.3A ~ 1.3A 1) Rebound Hard / Compression Soft : 0.3A 2) Rebound Soft / Compression Soft : 0.8A 3) Rebound Soft / Compression Hard : 1.3A - Rated voltage : 12V - Operating voltage : 10 ~ 16 V - PWM frequency : 500Hz OUTPUTS

62 Solenoid valve (Proportional type) [Construction] OUTPUTS

63 Solenoid valve (Proportional type) Reb.ChamberComp.ChamberBase Chamber Rebound valveCompression valve [Construction and operation] OUTPUTS

64 Solenoid valve (Proportional type) [Operation (HARD/SOFT mode)] OUTPUTS

65 Solenoid valve (Proportional type) [Operation (SOFT/SOFT mode)] OUTPUTS

66 Solenoid valve (Proportional type) [Operation (SOFT/HARD mode)] OUTPUTS

67 Solenoid valve (Proportional type) [Current data & output signal while SOFT/HARD control] [Output voltage signal][Applied current] OUTPUTS

68 Solenoid valve (Proportional type) [Current data & output signal while SOFT/SOFT control] [Output voltage signal][Applied current] OUTPUTS

69 Solenoid valve (Proportional type) [Current data & output signal while HARD/SOFT control] [Output voltage signal][Applied current] OUTPUTS

70 Solenoid valve (Proportional type) [F-V curve (Force - Velocity) & F-I curve (Force - Current)] OUTPUTS

71 OUTPUTS

72 SPEED SENSOR ALTERNATOR L LINE STEERING SENSOR ACCELERATION SENSOR (FR) DLCFAILURE C1106 C1259 C1212 C1279 C1278 C1281 DESCRIPTION L-Terminal outputs LOW for more than 10 seconds when the car speed is more than 40 Km/h. L-Terminal output voltage is more than 16V over 100 seconds. Steering output voltage is less than 0.5V or more than 4.6V over 30 seconds. L-Terminal output is HIGH. Throttle position sensor output duty is more than 35%, and the output less than 3km/h over 1 minute. Acceleration sensor output is less than 0.5V or more than 4.5V for 2 minutes. Acceleration sensor output keeps the same level at less than 1.9V or 3.1V for 2 minutes. DESCRIPTION Stop the control Stop the ride comfort control by Acceleration sensor Fix medium/Soft ACCELERATION SENSOR (FL) ACCELERATION SENSOR (RR) Stop the handling control by steering sensor OUTPUTS

73 DLCFAILUREDESCRIPTION The voltage at the 5V output terminal of the sensor is less than 0.8V for more than 20 seconds. DESCRIPTION Stop the control C1112 C2216 C2212 C2224 C2220 C2124 SENSOR POWER SOURCE VOLTAGE DAMPING FORCE CHANGE ACTUATOR FR DAMPING FORCE CHANGE ACTUATOR FL DAMPING FORCE CHANGE ACTUATOR RR DAMPING FORCE CHANGE ACTUATOR RL Harness wire is open or has a trouble. ACTUATOR RELAY Actuator relay order is different from actuator relay monitor result. Stop the control OUTPUTS

74 Battery : C1101 DIAGNOSTIC TROUBLE CODE Diagnostic trouble description - Low voltage (Engine run): Actuator operating voltage is more than 17V over 20sec. - High voltage (Engine run): Actuator operating voltage is more than 18V over 2sec. Action to be taken by ECU - Relay OFF Cancellation condition - ACG-L terminal output changes Low to High(9~16V) over 100msec.

75 Alternator L terminal : C1107, C1108 DTC: C1108 (Low voltage, Engine run) 1) Diagnostic trouble description: - Output voltage is less than 8.5V over 10sec When the car speed is more than 40km/h 2) Action to be taken by ECU: relay OFF 3) Cancellation condition: output voltage is more than 9.5V over 100msec. DTC: C1107 (High voltage, Engine run) 1) Diagnostic trouble description: - Output voltage is more than 16.5V over 100sec 2) Action to be taken by ECU: relay OFF 3) Cancellation condition: output voltage is less than 16V over 100msec. DIAGNOSTIC TROUBLE CODE

76 Actuator relay : C2124 Diagnostic trouble description - Low voltage when on (Engine run): Actuator operating voltage is less than 8.0V over 10sec. - High voltage when off (Engine off): Actuator operating voltage is more than 9.5V over 2sec when Key ON. Action to be taken by ECU - Relay OFF Cancellation condition - Low voltage when on (Engine run): ACG-L terminal output changes Low to High(9~16V) over 100msec. - High voltage when off (Engine off): ACG-L terminal output changes Low to High(9~16V) and 0V over 100msec. DIAGNOSTIC TROUBLE CODE

77 Speed sensor : C1212 DTC: C1212 (open/short, Engine run) Diagnostic trouble description: Throttle Position sensor output duty is more than 40%, and the output less than 3 km/h over 1 minutes. Action to be taken by ECU: Hard/Soft (F: 0.55A, R: 0.63 A) Cancellation condition: The car speed is more than 3km/h over 10msec. DIAGNOSTIC TROUBLE CODE

78 Steering sensor : C1259 DTC: C1259 (open/short, Engine run) Diagnostic trouble description: Sensor output voltage is less than 0.8V or more than 4.6V over 30sec Action to be taken by ECU: Stop the Roll control Cancellation condition: Right Output Voltage is over 10msec. DIAGNOSTIC TROUBLE CODE

79 Acceleration sensor : FR:C1279 FL:C1278 RR:C1281 Open/Short (Engine run) 1) Diagnostic trouble description: Sensor output is less than 0.5V or more than 4.5V for 2 minutes. 2) Action to be taken by ECU: Stop the Ride control 3) Cancellation condition: Acceleration sensor output is 2.5±0.2V over 10msec. Signal Error (Engine run) 1) Diagnostic trouble description: Sensor output keeps the same level at less than 1.9V or more than 3.1V for 2 minutes 2) Action to be taken by ECU: Stop the Ride control 3) Cancellation condition: Acceleration sensor output is 2.5±0.2V over 10msec. DIAGNOSTIC TROUBLE CODE

80 Solenoid valve (FR:C2216 FL:C2212 RR:C2224 RL:C2220) Solenoid valve open (Engine run) Diagnostic trouble description: Harness wire is open over 30sec.. Action to be taken by ECU: Relay OFF Cancellation condition: ACG-L terminal output changes Low to High(9~16V) over 100msec. DIAGNOSTIC TROUBLE CODE

81 Solenoid valve (Hi-scan display) DIAGNOSTIC TROUBLE CODE

82 ECSCM Hot at all time 15A Fuse 15 ON/S.T 15A Steering Sensor K lineECM/TCM 7 19 ECS switch ALTL 17 ECS Relay 118 ECS sport AUTO/HIGH SW.DIAGNOSISGROUNDTPS BATT. ECS RLY WARNING LAMP ECSCM POWER ST1ST2ALTL DIAGNOSTIC TROUBLE CODE

83 ECS - ECU Vehicle Sensor Stop Lamp LF G sensor LFRF LR RR Front actuatorRear actuator 63 RF G sensor Rear G sensor GND SNSR POWER SNSR SIGNAL SNSR SIGNAL SNSR SIGNAL DIAGNOSTIC TROUBLE CODE