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Adaptive Variable Suspension System (Diagnostics Codes & Circuit Tests): Overview Lexus GS III рестайлинг

Suspension Control Systems 11 illustrations ~664 words

DESCRIPTION

The acceleration sensor detects the amount of vertical force applied to the vehicle when accelerating or decelerating (G (up and down)). The acceleration sensors are mounted at 3 spots, which are in the absorber control ECU and at the front and rear of the cabin, to independently detect the amount of vertical force applied to the vehicle. The acceleration sensor converts the resistance, which changes according to the acceleration level, into an electric signal, and outputs it to the absorber control ECU.

The absorber control ECU detects the changes in each signal when performing the Test Mode check and outputs the Test Mode DTCs (C1791, C1792, C1793) if there is no change.

DTC No.DTC Detection ConditionTrouble Area
C1715 C1791When either of the following continues for 0.5 seconds or more: A signal of -9.8 m/s 2 to 9.8 m/s 2 or less is not input from the acceleration sensor to the absorber control ECU with the power switch ON (IG). The power source voltage of the right front acceleration sensor is 5.5 V or higher or 4.3 V or lower.Absorber control ECU (Houses right front acceleration sensor)
C1716 C1792When either of the following continues for 0.5 seconds or more: A signal of -9.8 m/s 2 to 9.8 m/s 2 or less is not input from the acceleration sensor to the absorber control ECU with the power switch ON (IG). The power source voltage of the left front acceleration sensor is 5.5 V or higher or 4.3 V or lower.Left front acceleration sensor Left front acceleration sensor circuit Absorber control ECU
C1717 C1793When either of the following continues for 0.5 seconds or more: A signal of -9.8 m/s 2 to 9.8 m/s 2 or less is not input from the acceleration sensor to the absorber control ECU with the power switch ON (IG). The power source voltage of the rear acceleration sensor (SBL3 terminal) is 5.5 V or higher or 4.3 V or lower.Rear acceleration sensor Rear acceleration sensor circuit Absorber control ECU

HINT

  1. DTC C1715 and C1791 are for the right front acceleration sensor.
  2. DTC C1716 and C1792 are for the left front acceleration sensor.
  3. DTC C1717 and C1793 are for the rear acceleration sensor.
  4. Since the right front acceleration sensor is built into the absorber control ECU, replace the absorber control ECU when DTCs C1715 and C1791 are output.

Scheme 17

Scheme 17: WIRING DIAGRAM
Scheme 17: WIRING DIAGRAM

The absorber control actuator changes the damping forces of the absorbers according to the signal output from the absorber control ECU.

DTC No.DTC Detection ConditionTrouble Area
C1725When either of the following is detected: An actuator open-circuit signal is detected for at least 1 second when the actuator operates. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.Right front absorber control actuator Right front absorber control actuator circuit Absorber control ECU
C1726When either of the following is detected: An actuator open-circuit signal is detected for at least 1 second when the actuator operates. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.Left front absorber control actuator Left front absorber control actuator circuit Absorber control ECU
C1727When either of the following is detected: An actuator open-circuit signal is detected for at least 1 second when the actuator operates. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.Right rear absorber control actuator Right rear absorber control actuator circuit Absorber control ECU
C1728When either of the following is detected: An actuator open-circuit signal is detected for at least 1 second when the actuator operates. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.Left rear absorber control actuator Left rear absorber control actuator circuit Absorber control ECU

Scheme 18

Scheme 18: WIRING DIAGRAM
Scheme 18: WIRING DIAGRAM

Scheme 19

Scheme 19
Scheme 19

The absorber control ECU outputs C1761 if any malfunction occurs in the absorber control ECU itself or a resistor in the CAN communication system.

DTC No.DTC Detection ConditionTrouble Area
C1761CAN communication resistor malfunction or internal absorber control ECU malfunction.CAN communication system Absorber control ECU
  1. The absorber control ECU inputs the signals from the steering control ECU via CAN communication.
  2. The fail-safe function prohibits roll posture control if any malfunction occurs in the steering control ECU. Refer to «FAIL-SAFE CHART»(ref-386964-S03220230582011022400000) .
DTC No.DTC Detection ConditionTrouble Area
C1773The fail flag signal is received from the steering control ECU for 5 seconds.VGRS system CAN communication system

Scheme 20

Scheme 20: WIRING DIAGRAM
Scheme 20: WIRING DIAGRAM
  1. This circuit provides power to operate the absorber control ECU.
  2. This DTC is stored when the B terminal voltage is as described in the DTC detection condition due to a malfunction in the power supply or a charging circuit such as the battery, alternator circuit, etc.
DTC No.DTC Detection ConditionTrouble Area
C1774The terminal B or battery voltage is below 10 V or above 16 V for 0.5 seconds.Battery Power source circuit Absorber control ECU

Scheme 21

Scheme 21: WIRING DIAGRAM
Scheme 21: WIRING DIAGRAM
  1. The speed sensor detects the wheel speed and transmits the appropriate vehicle speed signal to the absorber control ECU through the skid control ECU via CAN communication system.
  2. This DTC (C1776) is output if any malfunction exists in the speed sensor FR, FL, RR, or RL system.
DTC No.DTC Detection ConditionTrouble Area
C1776The speed sensor malfunction signal is received for 1 second or moreCAN communication system Brake control system Speed sensor circuit Absorber control system

Scheme 22

Scheme 22: WIRING DIAGRAM
Scheme 22: WIRING DIAGRAM
  1. The steering angle sensor detects the amount and direction of steering wheel movement and inputs these details to the absorber control ECU via CAN communication.
  2. The fail-safe function prohibits roll posture control if any malfunction occurs in the steering angle sensor circuit. Refer to «FAIL-SAFE CHART»(ref-386964-S03220230582011022400000) .
DTC No.DTC Detection ConditionTrouble Area
C1777Either steering angle sensor DTC or steering angle sensor power source DTC is detected for 5 seconds or moreSteering angle sensor Steering angle sensor circuit

Scheme 23

Scheme 23: WIRING DIAGRAM
Scheme 23: WIRING DIAGRAM
  1. The absorber control switch (EMS switch) is a switch which selects the damping force mode of each shock absorber.
  2. The absorber control ECU reads the changes in each signal when performing the Test Mode check and outputs the DTC (C1787) if there is no change.
DTC No.DTC Detection ConditionTrouble Area
C1787There is no change in the absorber control switch signal when performing the Test Mode check.Absorber control switch Absorber control switch circuit Absorber control ECU

Scheme 24

Scheme 24: WIRING DIAGRAM
Scheme 24: WIRING DIAGRAM

The absorber control ECU inputs signals from the skid control ECU, steering control ECU, steering angle sensor and hybrid control ECU via CAN communication. When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system first.

DTC No.DTC Detection ConditionTrouble Area
U0122Skid control ECU informs of CAN communication stop for 3 seconds or moreCAN communication line Skid control ECU
U0126Steering angle sensor informs of CAN communication stop for 3 seconds or moreCAN communication line Steering angle sensor
U0130Steering control ECU informs of CAN communication stop for 3 seconds or moreCAN communication line Steering control ECU
U0132CAN bus turns OFF 10 times in a rowAbsorber control ECU
U0293While driving at 30 km/h (19 mph), hybrid control ECU informs of CAN communication stop for 3 seconds or moreCAN communication line Hybrid control ECU
  1. Check the DTC and make sure that the normal system code is output. Refer to «DTC CHECK / CLEAR»(ref-386964-S15748959292011022400000) . If a malfunction code is output, refer to the "DIAGNOSTIC TROUBLE CODE CHART". Refer to «DIAGNOSTIC TROUBLE CODE CHART»(ref-386964-S33924158782011022400000) .
  2. If the absorber control ECU stores a DTC, the absorber control indicator light on the combination meter will come on.
  3. The absorber control ECU is connected to the combination meter via the CAN communication system and multiplex communication system.

Scheme 25

Scheme 25: WIRING DIAGRAM
Scheme 25: WIRING DIAGRAM

Refer to Absorber Control Indicator Light Remains ON. Refer to Absorber Control Indicator Light Remains ON .

The DTC output mode is set by connecting terminals TC and CG of DLC3.

The DTCs are displayed through blinking patterns of the absorber control indicator light.

Scheme 26

Scheme 26: WIRING DIAGRAM
Scheme 26: WIRING DIAGRAM

The signal check circuit detects any trouble in the sensor or switch signal which cannot be detected by the DTC check.

Connecting terminals TS and CG of the DLC3 starts the check.

Scheme 27

Scheme 27: WIRING DIAGRAM
Scheme 27: WIRING DIAGRAM

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