Vehicle Stability Control System (For Hatchback With Separate Type Yaw Rate Sensor) Trac Off Indicator Light Does Not Come On

Brake. Yaris. Ncp93, 131
Brake Control Dynamic Control Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK CAN COMMUNICATION SYSTEM

CHECK HARNESS AND CONNECTOR (CSW TERMINAL)

READ VALUE USING TECHSTREAM (TRAC/VSC OFF MODE)

INSPECT VSC OFF SWITCH

CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - VSC OFF SWITCH)

VEHICLE STABILITY CONTROL SYSTEM (for Hatchback with Separate Type Yaw Rate Sensor) - TRAC OFF Indicator Light does not Come ON


DESCRIPTION

The skid control ECU (brake actuator assembly) is connected to the combination meter via CAN communication.
Pressing the VSC OFF switch turns off traction control and pressing and holding this switch turns off traction and VSC controls. If traction control turns OFF, the TRAC OFF indicator light will come on.
If VSC and traction control turns OFF, the TRAC OFF indicator and VSC OFF indicator light will come on.
The TRAC OFF indicator light is illuminated when the TRAC control is prohibited by operating the VSC OFF switch.
By Pressing the VSC OFF switch for a short time, the TRAC OFF mode is activated, and the TRAC control is prohibited, and the TRAC OFF indicator light in the combination meter is illuminated.
By pressing the VSC OFF switch for 3 seconds or longer, the VSC OFF mode is activated, the VSC and TRAC controls are prohibited, and both the VSC OFF indicator light and the TRAC OFF indicator light are illuminated.

WIRING DIAGRAM

Refer to TRAC OFF Indicator Light Remains ON (YARIS_NCP93 RM00000452200YX_06.html)

INSPECTION PROCEDURE

NOTICE:
  1. When replacing the brake actuator assembly, perform zero point calibration (YARIS_NCP93 RM000000XHR07EX.html).
  2. Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.CHECK CAN COMMUNICATION SYSTEM

  1. Check if CAN communication system DTCs are output (YARIS_NCP93 RM000001RSW02LX.html).

Result
Result
Proceed to
DTC is not output
A
DTC is output
B


B
CHECK CAN COMMUNICATION SYSTEM (YARIS_NCP93 RM000001RSO05UX.html)
A


2.CHECK HARNESS AND CONNECTOR (CSW TERMINAL)

  1. Turn the ignition switch off.



    Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan).Vehicle Stability Control System (For Hatchback With Separate Type Yaw Rate Sensor) Trac Off Indicator Light Does Not Come On

  1. Disconnect the skid control ECU connector.

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

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A70-30 (CSW) - Body ground
    		VSC OFF Switch held on
    		Below 1 Ω
    A70-30 (CSW) - Body ground
    		VSC OFF Switch off (Not pressed)
    		10 kΩ or higher
Text in Illustration
*a
Front view of wire harness connector
(to skid control ECU)

  1. Reconnect the skid control ECU connector.



NG
Go to step 4
OK


3.READ VALUE USING TECHSTREAM (TRAC/VSC OFF MODE)

  1. Turn the ignition switch off.

  1. Connect the Techstream to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the Techstream on.

  1. Enter the following menus: Chassis / ABS/VSC/TRAC / Data List.

  1. According to the display on the Techstream, read the Data List.

    ABS/VSC/TRAC
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    TRAC/VSC Off Mode
    		TRAC/VSC off mode/Normal, TRC OFF, Unknown or VSC OFF
    		Normal: Normal mode
    TRC OFF: TRAC OFF mode
    Unknown: Unspecified
    VSC OFF: TRAC, VSC OFF mode
    		-

  1. Check that the mode display changes according to the VSC OFF switch operation.

    OK:
    Display changes according to the switch operation.


NG
REPLACE BRAKE ACTUATOR ASSEMBLY (YARIS_NCP93 RM000001BXP02KX.html)
OK

REPLACE COMBINATION METER ASSEMBLY (YARIS_NCP93 RM0000035EJ00BX.html)

4.INSPECT VSC OFF SWITCH

  1. Remove the VSC OFF switch (YARIS_NCP93 RM000001WZ202CX.html).

  1. Inspect the VSC OFF switch (YARIS_NCP93 RM000001WYZ02CX.html).

  1. Reconnect the VSC OFF switch connector.



NG
REPLACE VSC OFF SWITCH (YARIS_NCP93 RM000001WZ202CX.html)
OK


5.CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - VSC OFF SWITCH)

  1. Disconnect the skid control ECU (brake actuator assembly) connector and the VSC OFF switch connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A70-30 (CSW) - D142-6
    		Always
    		Below 1 Ω
    D142-3 - Body ground
    		Always
    		Below 1 Ω
    A70-30 (CSW) - Body ground
    		Always
    		10 kΩ or higher

  1. Reconnect the skid control ECU (brake actuator assembly) connector and the VSC OFF switch connector.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

CHECK FOR INTERMITTENT PROBLEMS (SYMPTOM SIMULATION) (YARIS_NCP93 RM000000XHS0AZX.html)