ACTIVE HEIGHT CONTROL SUSPENSION, Diagnostic DTC:C1718

DTC Code DTC Name
C1718 Pressure Sensor Circuit Malfunction

DESCRIPTION

This circuit is used for sending the data to detect the pressure output from the pump. The abnormality of the fluid pressure is judged by the ECU.

DTC Code Detecting Condition Trouble Area
C1718

When one of the following conditions is met:


  • When detecting an abnormal signal from the pressure sensor (pressure sensor terminal voltage of ECU is 0.3 V or less or 4.6 V or more) for 1 second.

  • When there is a pressure sensor power supply voltage malfunction.

  • When a pressure of 1 MPa (10.2 kgf/cm2, 145 psi) or more is placed on the pressure sensor for 20 seconds or more, no voltage is flowing to the height control pump and motor, and the vehicle height control is not operating, it is determined that there is a sensor stuck malfunction.

  • Harness or connector

  • Height control pump and motor (Pressure sensor)

  • Suspension control ECU

WIRING DIAGRAM

A015CBBE01

INSPECTION PROCEDURE

Note


  • 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 Click here.

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (PRESSURE SENSOR - SUSPENSION CONTROL ECU)

    Note

    When inspecting the wire harness between the suspension control ECU and pressure sensor, it is difficult to determine the malfunctioning area if there is a sensor power supply malfunction. Therefore, disconnect the connectors for the pressure sensor, the acceleration sensors (front RH, front LH) and fluid temperature sensor on the ECU side.


    1. Disconnect the i2 pressure sensor connector.

    2. Disconnect the K34 and K35 ECU connectors.

      A0156XAE01

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K35-10 (SPB) - i2-1 (SHB) Always Below 1 Ω
      K35-19 (SPG) - i2-3 (SHG) Always Below 1 Ω
      K35-20 (PACC) - i2-2 (PACC) Always Below 1 Ω
      K35-10 (SPB) - Body ground Always 10 kΩ or higher
      K35-19 (SPG) - Body ground Always 10 kΩ or higher
      K35-20 (PACC) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK SUSPENSION CONTROL ECU


    1. Connect the K34 and K35 suspension control ECU connectors.

    2. A015CCAE01

      Disconnect the i2 pressure sensor connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      i2-1 (SHB) - i2-3 (SHG) Engine switch on (IG) 4.75 to 5.25 V

    NG

    REPLACE SUSPENSION CONTROL ECU Click here

    OK

  3. CHECK PRESSURE SENSOR


    1. Connect the K34 and K35 suspension control ECU connectors.

    2. Connect the i2 pressure sensor connector.

    3. A015AT9E01

      Start the engine and push the up button of the height control switch to activate height control.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      K35-20 (PACC) - K35-19 (SPG) While height control is operating. 1.48 to 2.54 V

    NG

    REPLACE HEIGHT CONTROL PUMP AND MOTOR

    OK

    REPLACE SUSPENSION CONTROL ECU Click here