ACTIVE HEIGHT CONTROL SUSPENSION, Diagnostic DTC:C1792

DTC Code DTC Name
C1792 Height Control Switch Circuit (Test Mode DTC)

DESCRIPTION

This circuit sends a signal to the suspension control ECU in order to adjust the height to the selected height by the height control switch.

DTC Code Detection Condition Trouble Area
C1792 The test mode procedure is performed.

  • Harness or connector

  • Suspension control switch (Height control switch)

  • Suspension control ECU

WIRING DIAGRAM

A01574AE08

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. READ VALUE USING INTELLIGENT TESTER (HEIGHT CONTROL SWITCH (UP), HEIGHT CONTROL SWITCH (DOWN))


    1. Turn the engine switch off.

    2. Connect the intelligent tester to the DLC3.

    3. Turn the engine switch on (IG) and the tester on.

    4. Enter the following menus: Chassis / AHC / Data List.

    5. According to the display on the tester, read the Data List.

      AHC
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Height Control Switch(Up)

      Height control switch (Up) /

      ON or OFF

      ON: Up button of the height control switch is pushed.

      OFF: Height control switch is not pushed.

      		 -
      Height Control Switch(Down)

      Height control switch (Down) /

      ON or OFF

      ON: Down button of the height control switch is pushed.

      OFF: Height control switch is not pushed.

      		 -
      OK
      On the tester screen, item changes between ON and OFF according to switch operation.

    NG

    INSPECT SUSPENSION CONTROL SWITCH (HEIGHT CONTROL SWITCH) Click here

    OK

  2. TEST MODE INSPECTION


    1. Refer to the Test Mode Procedure and perform the signal check. Check that test mode DTC C1792 is cleared Click here.

      Result
      Result Proceed to
      DTC C1792 is not cleared A
      DTC C1792 is cleared B

    B

    USE SIMULATION METHOD TO CHECK Click here

    A

    REPLACE SUSPENSION CONTROL ECU Click here

  3. INSPECT SUSPENSION CONTROL SWITCH (HEIGHT CONTROL SWITCH)


    1. Remove the suspension control switch Click here.

    2. A015A02E02

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      8 (LO) - 16 (E) Down button of the height control switch is pushed. Below 1 Ω
      Height control switch is not pushed or the up button is pushed. 10 kΩ or higher
      7 (HI) - 16 (E) Up button of the height control switch is pushed. Below 1 Ω
      Height control switch is not pushed or the down button is pushed. 10 kΩ or higher

    NG

    REPLACE SUSPENSION CONTROL SWITCH Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (SUSPENSION CONTROL ECU - SWITCH AND BODY GROUND)

    A0159OLE05

    1. Disconnect the K34 ECU connector.

    2. Disconnect the V4 switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K34-20 (UPSW) - V4-7 (HI) Always Below 1 Ω
      K34-20 (UPSW) - Body ground Always 10 kΩ or higher
      K34-21 (DNSW) - V4-8 (LO) Always Below 1 Ω
      K34-21 (DNSW) - Body ground Always 10 kΩ or higher
      V4-16 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE SUSPENSION CONTROL ECU Click here