ADAPTIVE VARIABLE SUSPENSION SYSTEM, Diagnostic DTC:C1789

DTC Code DTC Name
C1789 Vehicle Identification Malfunction

DESCRIPTION


DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Note
C1789 Vehicle Identification Malfunction

Either condition is met:


  • The vehicle identification information is not stored.

  • Vehicle identification information that is different from the stored information is received 3 times.

  • The stop and start system setting availability stored value is not stored.

  • When stored stop and start system setting is OFF, setting is determined to be ON.

  • CAN communication system

  • Vehicle identification information

  • ECM

  • Absorber control ECU (front acceleration sensor RH)

 Does not come on -

CAUTION / NOTICE / HINT

Note


  • Before performing troubleshooting, inspect the connectors of related circuits.

  • If DTC C1781 (Suspension Control ECU Malfunction) is output at the same time, perform troubleshooting for C1781 first.

    Click here

  • If DTC C1782 (Power Source Voltage Malfunction) is output at the same time, perform troubleshooting for C1782 first.

    Click here

  • Before replacing the absorber control ECU (front acceleration sensor RH), perform all of the following:


    • Symptom simulation.

      Click here

    • DTC inspection.

      Click here

    • GTS inspection.

      Click here


      • If no malfunctions are found in other areas, replace the absorber control ECU (front acceleration sensor RH).

  • After replacing the absorber control ECU (front acceleration sensor RH) with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE


  1. CHECK FOR DTC (CAN COMMUNICATION SYSTEM)


    1. Check for DTCs.

      Click here


      Chassis > Air suspension > Trouble Codes
      Result
      Result Proceed to
      CAN DTCs are not output A
      CAN DTCs are output B

    B

    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) for LHD: Click here
    GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) for RHD: Click here

    A

  2. CHECK VEHICLE IDENTIFICATION INFORMATION STATUS


    1. Check that vehicle identification information has been stored.

      Click here

      Result
      Result Proceed to
      Information stored A
      Information not stored B

    B

    PERFORM VEHICLE IDENTIFICATION INFORMATION REGISTRATION Click here

    A

  3. READ VALUE USING GTS (STOP AND START LEARNING STATUS)


    1. Turn the engine switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the engine switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / Air suspension / Data List.


      Chassis > Air suspension > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Stop and Start Learning Status Learning status of stop and start setting availability after vehicle identification information registration is performed Unset, OFF or ON OFF When "Unset", DTC C1789 is output.

      Chassis > Air suspension > Data List
      Tester Display
      Stop and Start Learning Status

    6. Check the value displayed on the GTS.

      OK
      The display is as specified in the normal condition column.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE ABSORBER CONTROL ECU (FRONT ACCELERATION SENSOR RH) Click here

    OK

  4. CHECK RELATED PART


    1. If the DTC was output as a result of the replacement of a related part, replace the part with one that has a correct part number.

      Related Part ECM

      Note

      When removing a related part to check it, be sure to follow the appropriate procedures and precautions.

      Refer to the following procedures to remove the ECM.

      Click here

      Tech Tips

      If parts have not been replaced and DTC C1789 is output, there may be an internal malfunction in the absorber control ECU (front acceleration sensor RH). Therefore, replace the absorber control ECU (front acceleration sensor RH).

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      Chassis > Air suspension > Clear DTCs

    2. Turn the engine switch off.

    3. Check if DTC C1789 is output.

      Click here


      Chassis > Air suspension > Trouble Codes
      OK
      DTC C1789 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END

    NG

    REPLACE ABSORBER CONTROL ECU (FRONT ACCELERATION SENSOR RH) Click here