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 Memory
C1789 Vehicle Identification Malfunction

One of the following conditions 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.

  • Air suspension system setting availability stored value is not stored.

  • Received air suspension system availability value differs from stored value.

  • Conventional/Hybrid vehicle information is not stored.

  • Received conventional/hybrid vehicle information value differs from stored value.

  • Vehicle identification information

  • Hybrid vehicle control ECU assembly

  • CAN communication system

  • Absorber control ECU

 Does not come on

Yes

(Under some of the detection conditions (control map non-retrieval, air suspension system setting availability stored value is not stored, Conventional/Hybrid vehicle information is not stored and stop and start system setting availability stored value is not stored), DTC is not stored.)

CAUTION / NOTICE / HINT

Note


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

  • 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.

  • After replacing the absorber control ECU with a new one, perform registration of vehicle identification information.

    Click here

PROCEDURE


  1. CHECK FOR DTCS (CAN COMMUNICATION SYSTEM)


    1. Check for DTCs.

      Click here


      Chassis > Adaptive Variable Suspension System > Trouble Codes

      Tech Tips

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

      Result
      Result Proceed to
      C1781 and CAN communication malfunction DTC are not output A
      C1781 is output B
      CAN communication DTC is output C

    B

    GO TO C1781 Click here

    C

    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. READ VALUE USING GTS (VEHICLE STATUS)


    1. Turn the power switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / Adaptive Variable Suspension System / Data List.


      Chassis > Adaptive Variable Suspension System > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Vehicle Information (Conv/HV) Vehicle identification information (hybrid vehicle or except hybrid vehicle) Unknown, Conv or HV HV: When vehicle identification normal When "Unset", DTC C1789 is output.
      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.
      Air suspension Learning Status Learning status of air suspension system setting availability after vehicle identification information registration is performed Unset, OFF or ON

      ON: w/ Air suspension system

      OFF: w/o Air Suspension system

      		 When "Unset", DTC C1789 is output.

      Chassis > Adaptive Variable Suspension System > Data List
      Tester Display
      Vehicle Information (Conv/HV)
      Stop and Start Learning Status
      Air suspension 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 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 Hybrid Vehicle Control ECU Assembly

      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 hybrid vehicle control ECU assembly.

      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.

      Result
      Result Proceed to
      The related part has an incorrect part number. A
      The related part has the correct part number, or a related part and absorber control ECU have not been replaced. B

    A

    REPLACE RELATED PART WITH PART THAT HAS CORRECT PART NUMBER Click here

    B

    REPLACE ABSORBER CONTROL ECU Click here