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 (integration control and panel assembly).

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

  • Harness or connector

  • Height control switch (Integration control and panel assembly)

  • Suspension control ECU

WIRING DIAGRAM

B00195RE14

CAUTION / NOTICE / HINT

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 GTS (HEIGHT CONTROL SWITCH (UP), HEIGHT CONTROL SWITCH (DOWN))


    1. Turn the engine switch off.

    2. Connect the GTS to the DLC3.

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

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

    5. According to the display on the GTS, 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 height control switch pushed

      OFF: Height control switch not pushed

      		 -
      Height Control Switch(Down)

      Height control switch (Down) /

      ON or OFF

      ON: Down button of height control switch pushed

      OFF: Height control switch not pushed

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

    NG

    INSPECT INTEGRATION CONTROL AND PANEL ASSEMBLY (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

    A

    REPLACE SUSPENSION CONTROL ECU Click here

    B

    USE SIMULATION METHOD TO CHECK Click here

  3. INSPECT INTEGRATION CONTROL AND PANEL ASSEMBLY (HEIGHT CONTROL SWITCH)


    1. Remove the height control switch (integration control and panel assembly) Click here.

    2. Inspect the height control switch (integration control and panel assembly) Click here.


    NG

    REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY Click here

    OK

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

    B001AELE02
    *1 Rear view of wire harness connector: (to Suspension Control ECU)
    *2 Front view of wire harness connector: (to Integration Control and Panel Assembly)

    1. Disconnect the K30 ECU connector.

    2. Disconnect the V12 integration control and panel assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K30-20 (UPSW) - V12-9 (HI) Always Below 1 Ω
      K30-20 (UPSW) - Body ground Always 10 kΩ or higher
      K30-21 (DNSW) - V12-10 (LO) Always Below 1 Ω
      K30-21 (DNSW) - Body ground Always 10 kΩ or higher
      V12-1 (E) - Body ground Always Below 1 Ω

    OK

    REPLACE SUSPENSION CONTROL ECU Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR