Dtc C1731 Front Damping Force Control Actuator Rh Circuit Malfunction

Land Cruiser URJ200 URJ202 GRJ200 VDJ200 - SUSPENSION CONTROL

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (DAMPER STEP)

RECONFIRM DTC OUTPUT

CHECK HARNESS AND CONNECTOR (DAMPING FORCE CONTROL ACTUATOR - SUSPENSION CONTROL ECU)

INSPECT DAMPING FORCE CONTROL ACTUATOR

DTC C1731 Front Damping Force Control Actuator RH Circuit Malfunction

DTC C1732 Front Damping Force Control Actuator LH Circuit Malfunction

DTC C1733 Rear Damping Force Control Actuator RH Circuit Malfunction

DTC C1734 Rear Damping Force Control Actuator LH Circuit Malfunction

DESCRIPTION

The ECU sends a signal to the damping force control actuator to drive the rotary valve of the shock absorber changing the shock absorber damping force.


The actuator is driven electromagnetically by a step motor so that it can accurately follow the driving conditions that change frequently.

DTC CodeDetection ConditionTrouble Area
C1731When 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.
Harness or connector
Front shock absorber control valve RH (Front damping force control actuator RH)
Suspension control ECU
C1732When 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.
Harness or connector
Front shock absorber control valve LH (Front damping force control actuator LH)
Suspension control ECU
C1733When 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.
Harness or connector
Rear shock absorber control valve RH (Rear damping force control actuator RH)
Suspension control ECU
C1734When 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.
Harness or connector
Rear shock absorber control valve LH (Rear damping force control actuator LH)
Suspension control ECU

WIRING DIAGRAM

Dtc C1731 Front Damping Force Control Actuator Rh Circuit Malfunction. SUSPENSION CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

INSPECTION PROCEDURE

  • NOTICE:
Before performing troubleshooting, inspect the connectors of related circuits.
If the suspension control ECU or height control sensor is replaced, the vehicle height offset calibration must be performed ().
1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (DAMPER STEP)

According to the display on the intelligent tester, perform the Active Test.

Check if the damping force control actuator operates in accordance with the Active Test.

AHC
Tester DisplayTest PartControl RangeDiagnostic Note
Damper Step FRChanges front damper RH stepmin.: 1 step
max.: 16 step		The Damper Step item of the Data List changes to the step selected in the Active Test.
Damper Step FLChanges front damper LH stepmin.: 1 step
max.: 16 step		The Damper Step item of the Data List changes to the step selected in the Active Test.
Damper Step RRChanges rear damper RH stepmin.: 1 step
max.: 16 step		The Damper Step item of the Data List changes to the step selected in the Active Test.
Damper Step RLChanges rear damper LH stepmin.: 1 step
max.: 16 step		The Damper Step item of the Data List changes to the step selected in the Active Test.
  • OK:
  • The damping force control actuator operates.
NG
Go to step 3
OK
2.RECONFIRM DTC OUTPUT

Clear the DTCs ().

Perform a road test.

Check for DTCs.

Result
ResultProceed to
DTC is outputA
DTC is not outputB
B
USE SIMULATION METHOD TO CHECK ()
A
3.CHECK HARNESS AND CONNECTOR (DAMPING FORCE CONTROL ACTUATOR - SUSPENSION CONTROL ECU)

Check the front side damping force control actuator.


Disconnect the N9 and/or N11 actuator connector.

Disconnect the K36 ECU connector.

Dtc C1731 Front Damping Force Control Actuator Rh Circuit Malfunction. SUSPENSION CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

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

  • Standard Resistance:
  • for RH (C1731)
    Tester ConnectionConditionSpecified Condition
    K36-5 (FAR-) - N9-4 (FAR-)AlwaysBelow 1 Ω
    K36-5 (FAR-) - Body groundAlways10 kΩ or higher
    K36-6 (FAR+) - N9-1 (FAR+)AlwaysBelow 1 Ω
    K36-6 (FAR+) - Body groundAlways10 kΩ or higher
    K36-17 (FBR-) - N9-3 (FBR-)AlwaysBelow 1 Ω
    K36-17 (FBR-) - Body groundAlways10 kΩ or higher
    K36-18 (FBR+) - N9-5 (FBR+)AlwaysBelow 1 Ω
    K36-18 (FBR+) - Body groundAlways10 kΩ or higher
    N9-2 (E FR) - Body groundAlwaysBelow 1 Ω
  • for LH (C1732)
    Tester ConnectionConditionSpecified Condition
    K36-2 (FBL+) - N11-5 (FBL+)AlwaysBelow 1 Ω
    K36-2 (FBL+) - Body groundAlways10 kΩ or higher
    K36-3 (FAL-) - N11-4 (FAL-)AlwaysBelow 1 Ω
    K36-3 (FAL-) - Body groundAlways10 kΩ or higher
    K36-4 (FAL+) - N11-1 (FAL+)AlwaysBelow 1 Ω
    K36-4 (FAL+) - Body groundAlways10 kΩ or higher
    K36-12 (FBL-) - N11-3 (FBL-)AlwaysBelow 1 Ω
    K36-12 (FBL-) - Body groundAlways10 kΩ or higher
    N11-2 (E FL) - Body groundAlwaysBelow 1 Ω

Check the rear side damping force control actuator.


Disconnect the N6 and/or N8 actuator connector.

Disconnect the K35 ECU connector.

Dtc C1731 Front Damping Force Control Actuator Rh Circuit Malfunction. SUSPENSION CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

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

  • Standard Resistance:
  • for RH (C1733)
    Tester ConnectionConditionSpecified Condition
    K35-4 (RBR-) - N6-3 (RBR-)AlwaysBelow 1 Ω
    K35-4 (RBR-) - Body groundAlways10 kΩ or higher
    K35-5 (RAR+) - N6-1 (RAR+)AlwaysBelow 1 Ω
    K35-5 (RAR+) - Body groundAlways10 kΩ or higher
    K35-13 (RBR+) - N6-5 (RBR+)AlwaysBelow 1 Ω
    K35-13 (RBR+) - Body groundAlways10 kΩ or higher
    K35-14 (RAR-) - N6-4 (RAR-)AlwaysBelow 1 Ω
    K35-14 (RAR-) - Body groundAlways10 kΩ or higher
    N6-2 (E RR) - Body groundAlwaysBelow 1 Ω
  • for LH (C1734)
    Tester ConnectionConditionSpecified Condition
    K35-2 (RAL-) - N8-4 (RAL-)AlwaysBelow 1 Ω
    K35-2 (RAL-) - Body groundAlways10 kΩ or higher
    K35-3 (RAL+) - N8-1 (RAL+)AlwaysBelow 1 Ω
    K35-3 (RAL+) - Body groundAlways10 kΩ or higher
    K35-7 (RBL-) - N8-3 (RBL-)AlwaysBelow 1 Ω
    K35-7 (RBL-) - Body groundAlways10 kΩ or higher
    K35-8 (RBL+) - N8-5 (RBL+)AlwaysBelow 1 Ω
    K35-8 (RBL+) - Body groundAlways10 kΩ or higher
    N8-2 (E RL) - Body groundAlwaysBelow 1 Ω
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
4.INSPECT DAMPING FORCE CONTROL ACTUATOR

Check the front side damping force control actuator.


Connect the N9 and/or N11 front absorber control actuator connector.

Dtc C1731 Front Damping Force Control Actuator Rh Circuit Malfunction. SUSPENSION CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the K36 ECU connector.

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

  • Standard Resistance:
  • for RH (C1731)
    Tester ConnectionConditionSpecified Condition
    K36-5 (FAR-) - Body groundAlways12.0 to 13.6 Ω
    K36-6 (FAR+) - Body groundAlways12.0 to 13.6 Ω
    K36-17 (FBR-) - Body groundAlways12.0 to 13.6 Ω
    K36-18 (FBR+) - Body groundAlways12.0 to 13.6 Ω
  • for LH (C1732)
    Tester ConnectionConditionSpecified Condition
    K36-2 (FBL+) - Body groundAlways12.0 to 13.6 Ω
    K36-3 (FAL-) - Body groundAlways12.0 to 13.6 Ω
    K36-4 (FAL+) - Body groundAlways12.0 to 13.6 Ω
    K36-12 (FBL-) - Body groundAlways12.0 to 13.6 Ω

Check the rear side damping force control actuator.


Connect the N6 and/or N8 rear absorber control actuator connector.

Dtc C1731 Front Damping Force Control Actuator Rh Circuit Malfunction. SUSPENSION CONTROL. Land Cruiser URJ200 URJ202 GRJ200 VDJ200

Disconnect the K35 ECU connector.

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

  • Standard Resistance:
  • for RH (C1733)
    Tester ConnectionConditionSpecified Condition
    K35-4 (RBR-) - Body groundAlways12.0 to 13.6 Ω
    K35-5 (RAR+) - Body groundAlways12.0 to 13.6 Ω
    K35-13 (RBR+) - Body groundAlways12.0 to 13.6 Ω
    K35-14 (RAR-) - Body groundAlways12.0 to 13.6 Ω
  • for LH (C1734)
    Tester ConnectionConditionSpecified Condition
    K35-2 (RAL-) - Body groundAlways12.0 to 13.6 Ω
    K35-3 (RAL+) - Body groundAlways12.0 to 13.6 Ω
    K35-7 (RBL-) - Body groundAlways12.0 to 13.6 Ω
    K35-8 (RBL+) - Body groundAlways12.0 to 13.6 Ω
Result
ResultProceed to
OKA
Front damping force control actuator RH malfunctionB
Front damping force control actuator LH malfunctionC
Rear damping force control actuator RH malfunctionD
Rear damping force control actuator LH malfunctionE
B
REPLACE FRONT SHOCK ABSORBER CONTROL VALVE RH ()
C
REPLACE FRONT SHOCK ABSORBER CONTROL VALVE LH ()
D
REPLACE REAR SHOCK ABSORBER CONTROL VALVE RH ()
E
REPLACE REAR SHOCK ABSORBER CONTROL VALVE LH ()
A
REPLACE SUSPENSION CONTROL ECU ()