AIR SUSPENSION SYSTEM, Diagnostic DTC:C1792

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

DESCRIPTION

Pressing the height control switch (driver seat) while the power switch on (READY) for approximately 1 second switches modes. If the switch is pressed while the vehicle height is changing, vehicle height control will be cancelled.

DTC No. DTC Detecting Condition Trouble Area
C1792 Detected only during Test Mode.

  • Height control switch (driver seat)

  • Harness or connector

  • Suspension control ECU

WIRING DIAGRAM

A01NFVZE03

INSPECTION PROCEDURE

Note


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

  • Before replacing the suspension control ECU, perform all of the following again: 1) symptom simulation Click here; 2) DTC inspection Click here; and 3) Intelligent tester inspection (Data List or Active Test) Click here. If no malfunctions are found in other areas, replace the suspension control ECU.

  • If the suspension control ECU is replaced, the vehicle height offset calibration and registration of vehicle identification information must be performed Click here and Click here

PROCEDURE


  1. INSPECT HEIGHT CONTROL SWITCH (DRIVER SEAT)


    1. A01NDY3E03
      Text in Illustration
      *1

      Component without harness connected

      (Height Control Switch)

      Disconnect the height control switch (driver seat) connector.

    2. Measure the resistance according to the values in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      1 (LSW) - 8 (IGH) Height control switch while pressing "UP" button 10 kΩ or higher
      Height control switch while pressing "DOWN" button Below 1 Ω
      Neutral position 10 kΩ or higher
      2 (HSW) - 8 (IGH) Height control switch while pressing "UP" button Below 1 Ω
      Height control switch while pressing "DOWN" button 10 kΩ or higher
      Neutral position 10 kΩ or higher

    NG

    REPLACE HEIGHT CONTROL SWITCH (DRIVER SEAT) Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (HEIGHT CONTROL SWITCH - ECU AND BODY GROUND)


    1. A01NGDOE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Height Control Switch)
      *2

      Rear view of wire harness connector

      (to Suspension Control ECU)

      Disconnect the A56 ECU connector.

    2. Disconnect the F24 height control switch (driver seat) connector.

    3. Measure the resistance according to the values in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      F24-1 (LSW) - A56-14 (DNSW) Always Below 1 Ω
      F24-2 (HSW) - A56-15 (UPSW) Always Below 1 Ω
      A56-14 (DNSW) - Body ground Always 10 kΩ or higher
      A56-15 (UPSW) - Body ground Always 10 kΩ or higher
      Result
      Condition Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    B

    REPLACE SUSPENSION CONTROL ECU (for RHD) Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    A

    REPLACE SUSPENSION CONTROL ECU (for LHD) Click here