Dtc C1725 Front Damping Force Control Actuator Rh Circuit

Suspension & Axle. Lexus Gs430, Gs300. Uzs190 Grs190
Suspension Control. Lexus Gs430, Gs300. Uzs190 Grs190

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT ABSORBER CONTROL ACTUATOR OPERATION

RECONFIRM DTC

CHECK HARNESS AND CONNECTOR (ABSORBER CONTROL ACTUATOR CIRCUIT)

INSPECT ABSORBER CONTROL ACTUATOR (EACH ABSORBER CONTROL ACTUATOR)

RECONFIRM DTC

DTC C1725 Front Damping Force Control Actuator RH Circuit

DTC C1726 Front Damping Force Control Actuator LH Circuit

DTC C1727 Rear Damping Force Control Actuator RH Circuit

DTC C1728 Rear Damping Force Control Actuator LH Circuit


DESCRIPTION

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 Condition
Trouble Area
C1725
  1. When either of the following is detected:
    1. An actuator open-circuit signal is detected for at least 1 second when the actuator operates.
    2. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.
  1. Right front absorber control actuator
  2. Right front absorber control actuator circuit
  3. Absorber control ECU
C1726
  1. When either of the following is detected:
    1. An actuator open-circuit signal is detected for at least 1 second when the actuator operates.
    2. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.
  1. Left front absorber control actuator
  2. Left front absorber control actuator circuit
  3. Absorber control ECU
C1727
  1. When either of the following is detected:
    1. An actuator open-circuit signal is detected for at least 1 second when the actuator operates.
    2. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.
  1. Right rear absorber control actuator
  2. Right rear absorber control actuator circuit
  3. Absorber control ECU
C1728
  1. When either of the following is detected:
    1. An actuator open-circuit signal is detected for at least 1 second when the actuator operates.
    2. An actuator short-circuit signal is consecutively detected 8 times when the actuator operates.
  1. Left rear absorber control actuator
  2. Left rear absorber control actuator circuit
  3. Absorber control ECU

WIRING DIAGRAM


Lexus Gs430, Gs300. Uzs190 Grs190.Suspension Control.Adaptive Variable Suspension System. Dtc C1725 Front Damping Force Control Actuator Rh Circuit


INSPECTION PROCEDURE

NOTICE:
When replacing the absorber control ECU, check the acceleration sensor assembly signal after replacement (Click here).
HINT:
  1. Check the condition of each related circuit connector before troubleshooting (Click here).
  2. When C1774 is output, inspect and repair the trouble areas indicated by C1774 first (Click here).
1.INSPECT ABSORBER CONTROL ACTUATOR OPERATION

  1. Connect the intelligent tester to DLC3.

  1. Turn the engine switch on (IG) and turn the intelligent tester main switch on.

  1. Select "Active Test" mode on the intelligent tester (Click here).

    Active Test: EMS
    Item
    		Vehicle Condition / Test Details
    		Diagnostic Note
    Damper Step FR
    		Changes damper step / min.: 1 step, max.: 17 step
    		Shock absorber hardens as damper step increases
    Damper Step FL
    		Changes damper step / min.: 1 step, max.: 17 step
    		Shock absorber hardens as damper step increases
    Damper Step RR
    		Changes damper step / min.: 1 step, max.: 17 step
    		Shock absorber hardens as damper step increases
    Damper Step RL
    		Changes damper step / min.: 1 step, max.: 17 step
    		Shock absorber hardens as damper step increases

  1. Check if the absorber control actuator operates to harden the suspension with the intelligent tester.

    OK:
    The absorber control actuator operates.
    HINT:
    The operation of the absorber control actuator can be checked at OPERATION CHECK (Click here).
    OK:
    The absorber control actuator operates normally.


NG
Go to step 3
OK


2.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Perform a road test.

  1. Check that the same DTC is recorded (Click here).

    Result:

    Result
    		Proceed To
    DTC is output
    		A
    DTC is output (When troubleshooting accordance with the PROBLEM SYMPTOMS TABLE)
    		B
    DTC is not output
    		C


B
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C
END
A

REPLACE ABSORBER CONTROL ECU

3.CHECK HARNESS AND CONNECTOR (ABSORBER CONTROL ACTUATOR CIRCUIT)


    Lexus Gs430, Gs300. Uzs190 Grs190.Suspension Control.Adaptive Variable Suspension System. Dtc C1725 Front Damping Force Control Actuator Rh Circuit

  1. Disconnect the absorber control ECU connector and absorber control actuator connector.

  1. Measure the resistance according to the value(s) in the table below.

    Resistance:
    C1725 (Front LH):
    Tester Connection
    		Specified Condition
    A39-5 (FAL+) - A12-2 (A+)
    		Below 1 Ω
    A39-14 (FAL-) - A12-5 (A-)
    		Below 1 Ω
    A39-6 (FBL+) - A12-1 (B+)
    		Below 1 Ω
    A39-16 (FBL-) - A12-4 (B-)
    		Below 1 Ω
    A39-5 (FAL+) - Body ground
    		10 kΩ or higher
    A39-6 (FBL+) - Body ground
    		10 kΩ or higher
    A39-14 (FAL-) - Body ground
    		10 kΩ or higher
    A39-16 (FBL-) - Body ground
    		10 kΩ or higher
    A12-3 (E) - Body ground
    		Below 1 Ω
    Resistance:
    C1726 (Front RH):
    Tester Connection
    		Specified Condition
    A39-1 (FAR+) - A27-2 (A+)
    		Below 1 Ω
    A39-2 (FAR-) - A27-5 (A-)
    		Below 1 Ω
    A39-3 (FBR+) - A27-1 (B+)
    		Below 1 Ω
    A39-4 (FBR-) - A27-4 (B-)
    		Below 1 Ω
    A39-1 (FAR+) - Body ground
    		10 kΩ or higher
    A39-2 (FAR-) - Body ground
    		10 kΩ or higher
    A39-3 (FBR+) - Body ground
    		10 kΩ or higher
    A39-4 (FBR-) - Body ground
    		10 kΩ or higher
    A27-3 (E) - Body ground
    		Below 1 Ω
    Resistance:
    C1727 (Rear LH):
    Tester Connection
    		Specified Condition
    V2-6 (RAL+) - W27-2 (A+)
    		Below 1 Ω
    V2-7 (RAL-) - W27-5 (A-)
    		Below 1 Ω
    V2-8 (RBL+) - W27-1 (B+)
    		Below 1 Ω
    V2-9 (RBL-) - W27-4 (B-)
    		Below 1 Ω
    V2-6 (RAL+) - Body ground
    		10 kΩ or higher
    V2-7 (RAL-) - Body ground
    		10 kΩ or higher
    V2-8 (RBL+) - Body ground
    		10 kΩ or higher
    V2-9 (RBL-) - Body ground
    		10 kΩ or higher
    W27-3 (E) - Body ground
    		Below 1 Ω
    Resistance:
    C1728 (Rear RH):
    Tester Connection
    		Specified Condition
    V2-2 (RAR+) - V24-2 (A+)
    		Below 1 Ω
    V2-3 (RAR-) - V24-5 (A-)
    		Below 1 Ω
    V2-4 (RBR+) - V24-1 (B+)
    		Below 1 Ω
    V2-5 (RBR-) - V24-4 (B-)
    		Below 1 Ω
    V2-2 (RAR+) - Body ground
    		10 kΩ or higher
    V2-3 (RAR-) - Body ground
    		10 kΩ or higher
    V2-4 (RBR+) - Body ground
    		10 kΩ or higher
    V2-5 (RBR-) - Body ground
    		10 kΩ or higher
    V24-3 (E) - Body ground
    		Below 1 Ω


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (ABSORBER CONTROL ACTUATOR TO ABSORBER CONTROL ECU)
OK


4.INSPECT ABSORBER CONTROL ACTUATOR (EACH ABSORBER CONTROL ACTUATOR)


    Lexus Gs430, Gs300. Uzs190 Grs190.Suspension Control.Adaptive Variable Suspension System. Dtc C1725 Front Damping Force Control Actuator Rh Circuit

  1. SHAFT STOP POSITION CHECK

    1. Remove the absorber control actuator (Click here for front, Click here for rear).

    2. Connect the connector to the absorber control actuator.

    3. Check absorber control actuator operation (Click here).

      1. Shift to the Test Mode and start the engine.
      2. Check the shaft rotation when depressing the brake pedal.
      OK:
      The shaft rotates by 15°.
      HINT:
      The shaft rotates from the hard to soft position by 15° up to a maximum angle of 120° every time the brake pedal is depressed.

  1. ACTUATOR CHECK

    1. Disconnect the absorber control actuator connector.

    2. Measure the resistance according to the value(s) in the table below.

      Resistance:
      Tester Connection
      		Specified Condition
      1 (B+) - 3 (GND)
      		12.0 to 12.8 Ω
      2 (A+) - 3 (GND)
      		12.0 to 12.8 Ω
      4 (B-) - 3 (GND)
      		12.0 to 12.8 Ω
      5 (A-) - 3 (GND)
      		12.0 to 12.8 Ω


NG
REPLACE ABSORBER CONTROL ACTUATOR
OK


5.RECONFIRM DTC

  1. Clear the DTC (Click here).

  1. Perform a road test.

  1. Check that the same DTC is recorded (Click here).

    HINT:
    Reinstall the sensor connector, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

    Result:

    Result
    		Proceed To
    DTC is output
    		A
    DTC is output (When troubleshooting accordance with the PROBLEM SYMPTOMS TABLE)
    		B
    DTC is not output
    		C


B
PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE

C
END
A

REPLACE ABSORBER CONTROL ECU