ADAPTIVE VARIABLE SUSPENSION SYSTEM, Diagnostic DTC:C1789

DTC Code DTC Name
C1789 Vehicle Identification Malfunction

DESCRIPTION

When the absorber control ECU has not acquired the vehicle identification information, DTC C1789 is stored. When the vehicle identification information is correctly acquired, this DTC is cleared. Vehicle identification information is automatically acquired when the system enters test mode.

If an incorrect ECM is installed, the vehicle information will not match and DTC C1789 will be stored.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate
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.

  • CAN communication system

  • Vehicle identification information

  • ECM

  • Absorber control ECU

 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, 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.

  • When the absorber control ECU is replaced, switch to test mode and check that all test mode DTCs are cleared when their respective deletion conditions are met.

    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) 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. 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. Therefore, replace the absorber control ECU.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  4. 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 Click here