Anti-Lock Brake System (For Hatchback) Abs Warning Light Remains On

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

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED

CHECK CAN COMMUNICATION SYSTEM

INSPECT BATTERY

CHECK TERMINAL VOLTAGE (IG1 TERMINAL)

CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

READ VALUE USING TECHSTREAM (ABS WARNING LIGHT)

REPLACE COMBINATION METER ASSEMBLY

CHECK COMBINATION METER ASSEMBLY

ANTI-LOCK BRAKE SYSTEM (for Hatchback) - ABS Warning Light Remains ON


DESCRIPTION

The skid control ECU (brake actuator assembly) is connected to the combination meter via CAN communication.
If any of the following is detected, the ABS warning light remains on:
  1. The skid control ECU (brake actuator assembly) connectors are disconnected from the skid control ECU (brake actuator assembly).
  2. There is a malfunction in the skid control ECU (brake actuator assembly) internal circuit.
  3. There is an open in the harness between the combination meter and the skid control ECU (brake actuator assembly).
  4. The ABS control system is defective.
HINT:
In some cases, the Techstream cannot be used when the skid control ECU (brake actuator assembly) is abnormal.

WIRING DIAGRAM


Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan).Anti-Lock Brake System (For Hatchback) Abs Warning Light Remains On


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.CHECK IF SKID CONTROL ECU CONNECTOR IS SECURELY CONNECTED

  1. Check if the skid control ECU connector is securely connected.

    OK:
    The connector is securely connected.


NG
CONNECT CONNECTOR TO ECU CORRECTLY
OK


2.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


3.INSPECT BATTERY

  1. Check the battery voltage.

    Standard voltage:
    11 to 14 V


NG
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (YARIS_NCP93 RM000001GNJ010X.html)
OK


4.CHECK TERMINAL VOLTAGE (IG1 TERMINAL)

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

  1. Turn the ignition switch to ON.



    Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan).Anti-Lock Brake System (For Hatchback) Abs Warning Light Remains On

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A71-34 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Skid control ECU)

  1. Turn the ignition switch off.



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
OK


5.CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)


    Yaris. Ncp93, 131.Brake Control Dynamic Control Systems.Anti-Lock Brake System (For Sedan).Anti-Lock Brake System (For Hatchback) Abs Warning Light Remains On

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A71-1 (GND1) - Body ground
    		Always
    		Below 1 Ω
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Skid control ECU)

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



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT)
OK


6.READ VALUE USING TECHSTREAM (ABS WARNING LIGHT)

  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
    ABS Warning Light
    		ABS warning light / OFF or ON
    		OFF
    		-

  1. When performing the ABS Warning Light Active Test, check ABS Warning Light in the Data List.


ABS/VSC/TRAC
Tester Display
Test Part
Control Range
Diagnostic Note
ABS Warning Light
ABS warning light
Warning light ON/OFF
Observe the combination meter.

Result
Result
Proceed to
Data List Display
Data List Display when Performing Active Test ON/OFF Operation
ON
Changes between ON and OFF
A
Does not change between ON and OFF
B
OFF
Changes between ON and OFF
A
Does not change between ON and OFF
B


B
REPLACE BRAKE ACTUATOR ASSEMBLY (YARIS_NCP93 RM000001BXP02KX.html)
A


7.REPLACE COMBINATION METER ASSEMBLY

  1. Turn the ignition switch off.

  1. Replace the combination meter assembly (YARIS_NCP93 RM0000035EJ00BX.html).


NEXT


8.CHECK COMBINATION METER ASSEMBLY

  1. Connect the Techstream to the DLC3.

  1. Perform Active Test of the combination meter assembly using the Techstream (YARIS_NCP93 RM000001F8Q018X.html).

    OK:
    The ABS warning light turns on or off in accordance with the Techstream.


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

CHECK CAN COMMUNICATION SYSTEM (YARIS_NCP93 RM000001RSO05UX.html)