VEHICLE STABILITY CONTROL SYSTEM > Brake Warning Light Remains ON

for Preparation Click here


DESCRIPTION

The skid control ECU is connected to the combination meter via CAN communication.
If any of the following is detected, the brake warning light remains on:
  1. The skid control ECU connector is disconnected from the skid control ECU.
  2. The brake fluid level is insufficient.
  3. The parking brake is applied.
  4. EBD operation is not possible.

WIRING DIAGRAM


C212081E01


INSPECTION PROCEDURE

NOTICE:
When replacing the brake actuator assembly, perform zero point calibration (Click here).

1.CHECK CAN COMMUNICATION SYSTEM

  1. Check if CAN communication system DTCs are output (Click here).
    Result 
    Result
    		Proceed to
    DTC not output
    		A
    DTC output
    		B



B
CHECK CAN COMMUNICATION SYSTEM (Click here)
A


2.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


3.INSPECT BATTERY

  1. Check the battery voltage.

    Standard voltage:
    11 to 14 V



NG
CHECK OR REPLACE CHARGING SYSTEM OR BATTERY (Click here)
OK


4.INSPECT SKID CONTROL ECU (IG1 TERMINAL)

  1. Disconnect the A16 or A17 skid control ECU connector.

  1. Turn the ignition switch to ON.



    E175972E15

  1. Measure the voltage according to the value(s) in the table below.
    Text in Illustration 
    *A
    		for LHD
    *B
    		for RHD
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

    Standard Voltage:
    for LHD 
    Tester Connection
    		Switch Condition
    		Specified Condition
    A16-34 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V
    for RHD 
    Tester Connection
    		Switch Condition
    		Specified Condition
    A17-34 (IG1) - Body ground
    		Ignition switch ON
    		11 to 14 V

    Result 
    Result
    		Proceed to
    OK
    		A
    NG (w/ Stop and Start System)
    		B
    NG (w/o Stop and Start System)
    		C



B
GO TO STOP AND START SYSTEM (Click here)

C
REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT)
A


5.INSPECT SKID CONTROL ECU (GND TERMINAL)

  1. Turn the ignition switch off.



    E175972E14

  1. Measure the resistance according to the value(s) in the table below.
    Text in Illustration 
    *A
    		for LHD
    *B
    		for RHD
    *1
    		Front view of wire harness connector
    (to Skid Control ECU)

    Standard Resistance:
    for LHD 
    Tester Connection
    		Condition
    		Specified Condition
    A16-1 (GND1) - Body ground
    		Always
    		Below 1 Ω
    for RHD 
    Tester Connection
    		Condition
    		Specified Condition
    A17-1 (GND1) - Body ground
    		Always
    		Below 1 Ω



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


6.READ VALUE USING INTELLIGENT TESTER (PARKING BRAKE SWITCH)

  1. Reconnect the skid control ECU connector.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

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

    ABS/VSC/TRC (Skid Control ECU) 
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Parking Brake SW
    		Parking brake switch / ON or OFF
    		ON: Parking brake applied
    OFF: Parking brake released
    		-

  1. Using the intelligent tester, check the input of the switch operation when the parking brake pedal is operated.

    OK:
    When the parking brake is operated, the display changes as shown above.



NG
Go to step 12
OK


7.INSPECT BRAKE FLUID LEVEL WARNING SWITCH


    C196171E01

  1. Turn the ignition switch off.
    Text in Illustration 
    *1
    		Component with out harness connected
    (Brake Fluid Level Warning Switch)

  1. Remove the reservoir filler cap and strainer.

  1. Disconnect the brake fluid level warning switch connector.

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

    HINT:
    A float is located inside the reservoir. Its position can be changed by increasing or decreasing the level of brake fluid.

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    1 - 2
    		Switch OFF (Float up)
    		10 kΩ or higher
    1 - 2
    		Switch ON (Float down)
    		Below 1 Ω

    HINT:
    If there is no problem after finishing the above check, adjust the brake fluid level to the MAX level.



NG
REPLACE BRAKE MASTER CYLINDER RESERVOIR ASSEMBLY (BRAKE FLUID LEVEL WARNING SWITCH) (Click here)
OK


8.CHECK HARNESS AND CONNECTOR (COMBINATION METER - BRAKE FLUID LEVEL WARNING SWITCH)


  1. Disconnect the D2 combination meter connector.


    C197051E01


    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Brake Fluid Level Warning Switch)
    		*2
    		Front view of wire harness connector
    (to Combination Meter)

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    D2-7 (SW) - A24-1
    		Always
    		Below 1 Ω
    D2-7 (SW) - Body ground
    		Always
    		10 kΩ or higher
    A24-2 - Body ground
    		Always
    		Below 1 Ω



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


9.INSPECT COMBINATION METER ASSEMBLY

  1. Connect the intelligent tester to the DLC3.

  1. Perform Active Test of the combination meter using the intelligent tester (Click here).

    OK:
    The brake warning light turns ON or OFF in accordance with the intelligent tester.

    HINT:
    Reinstall the connectors and restore the vehicle to its prior condition before checking the combination meter.



NG
Go to step 10
OK

REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)  

10.REPLACE COMBINATION METER ASSEMBLY

  1. Turn the ignition switch off.

  1. Replace the combination meter (Click here).


NEXT


11.INSPECT COMBINATION METER ASSEMBLY

  1. Connect the intelligent tester to the DLC3.

  1. Perform Active Test of the combination meter using the intelligent tester (Click here).

    OK:
    The brake warning light turns ON or OFF in accordance with the intelligent tester.



NG
REPLACE BRAKE ACTUATOR ASSEMBLY (Click here)
OK

END 

12.INSPECT PARKING BRAKE SWITCH


    C212088E01

  1. Turn the ignition switch off.
    Text in Illustration 
    *1
    		Component without harness connected
    (Parking Brake Switch)

  1. Disconnect the parking brake switch connector.

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

    Standard Resistance:
    Tester Connection
    		Switch Condition
    		Specified Condition
    1 - Body ground
    		Parking brake switch ON
    (Switch pin free)
    		Below 1 Ω
    1 - Body ground
    		Parking brake switch OFF
    (Switch pin pushed in)
    		10 kΩ or higher



NG
REPLACE PARKING BRAKE SWITCH (Click here)
OK


13.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - PARKING BRAKE SWITCH)


  1. Disconnect the 3C instrument panel junction block assembly connector.


    C196168E02


    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Parking Brake Switch)
    		*2
    		Front view of wire harness connector
    (to Instrument Panel Junction Block Assembly)

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3C-33 (PKB) - D52-1
    		Always
    		Below 1 Ω
    3C-33 (PKB) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


14.CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - MAIN BODY ECU)


  1. Remove the main body ECU from the instrument panel junction block assembly.


    C196169E03


    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Instrument Panel Junction Block Assembly)
    		*2
    		Front view of wire harness connector
    (to Main Body ECU)

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    3C-33 - D42-12 (PKB)
    		Always
    		Below 1 Ω
    3C-33 - Body ground
    		Always
    		10 kΩ or higher



NG
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
OK

REPLACE MAIN BODY ECU