VEHICLE STABILITY CONTROL SYSTEM, Diagnostic DTC:C1379

DTC Code DTC Name
C1379 Downhill Assist Control Switch Malfunction (Test Mode DTC)

DESCRIPTION

DTC C1379 is cleared when the downhill assist control switch sends a downhill assist control operation signal or when test mode ends.

DTC No. Detection Item DTC Detection Condition Trouble Area
C1379 Downhill Assist Control Switch Malfunction (Test Mode DTC) Stored only during test mode.

  • Downhill assist control switch

  • Harness or connector

  • Skid control ECU (Brake actuator assembly)

WIRING DIAGRAM

A01V76QE04
*a Downhill Assist Control Switch
*b Skid Control ECU (Brake Actuator Assembly)

CAUTION / NOTICE / HINT

Note

When replacing the skid control ECU (brake actuator assembly), perform zero point calibration.

Click here

PROCEDURE


  1. READ VALUE USING GTS (DOWNHILL ASSIST CONTROL SW)


    1. Turn the ignition switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON.

    4. Turn the GTS on.

    5. Enter the following menus: Chassis / ABS/VSC/TRC / Data List.

    6. Check the Data List for proper functioning of the downhill assist control switch.


      Chassis > ABS/VSC/TRC > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Downhill Assist Control SW Downhill assist control switch ON or OFF

      OFF: Downhill assist control switch off

      ON: Downhill assist control switch on

      		 -

      Chassis > ABS/VSC/TRC > Data List
      Tester Display
      Downhill Assist Control SW
      OK
      The GTS displays ON or OFF according to downhill assist control switch operation.
      Result
      Result
      OK
      NG

    NG

    INSPECT DOWNHILL ASSIST CONTROL SWITCH Click here

    OK

  2. CHECK TEST MODE DTC


    1. Perform the downhill assist control switch check in the Test Mode Procedure.

      Click here


      Chassis > ABS/VSC/TRC > Utility
      Tester Display
      Signal Check
      OK
      Test mode DTC C1379 is cleared.
      Result
      Result
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

  3. INSPECT DOWNHILL ASSIST CONTROL SWITCH


    1. Remove the downhill assist control switch.

      Click here

    2. Inspect the downhill assist control switch.

      Click here

      Result
      Result
      OK
      NG

    NG

    REPLACE DOWNHILL ASSIST CONTROL SWITCH Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (BRAKE ACTUATOR ASSEMBLY - DOWNHILL ASSIST CONTROL SWITCH)


    1. Disconnect the A64 skid control ECU (brake actuator assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A64-29 (HDCS) - G29-4 Always Below 1 Ω
      A64-29 (HDCS) or G29-4 - Body ground Always 10 kΩ or higher
      G29-1 - Body ground Always Below 1 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR