Vehicle Stability Control System (For Hydraulic Brake Booster) Brake Warning Light Remains On


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK DTC

CHECK CAN COMMUNICATION LINE

READ VALUE USING INTELLIGENT TESTER (PARKING BRAKE SW)

READ VALUE USING INTELLIGENT TESTER (BRAKE WARNING LIGHT)

INSPECT PARKING BRAKE SWITCH

CHECK HARNESS AND CONNECTOR (PARKING BRAKE SWITCH - MAIN BODY ECU)

VEHICLE STABILITY CONTROL SYSTEM (for Hydraulic Brake Booster) - Brake Warning Light Remains ON


DESCRIPTION

The brake warning light comes on when brake fluid is insufficient, the parking brake is applied or the EBD is defective.

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System.Vehicle Stability Control System (For Hydraulic Brake Booster) Brake Warning Light Remains On


INSPECTION PROCEDURE

NOTICE:
When replacing the master cylinder solenoid, perform calibration (LandCruiser RM00000452J00ZX.html).
1.CHECK DTC

  1. Check for DTCs (LandCruiser RM0000046KV016X.html).

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


B
REPAIR CIRCUITS INDICATED BY OUTPUT DTCS (LandCruiser RM0000045Z601DX.html)
A


2.CHECK CAN COMMUNICATION LINE

  1. Turn the ignition switch off.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Select CAN Bus Check from the System Selection Menu screen and follow the prompts on the screen to inspect the CAN bus (for LHD: LandCruiser RM000000WIB0ECX.html, for RHD: LandCruiser RM000000WIB0EEX.html).

    OK:
    CAN Bus Check indicates no malfunctions in CAN communication.
    Result
    Result
    		Proceed to
    OK
    		A
    NG (for LHD)
    		B
    NG (for RHD)
    		C


B
GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) (LandCruiser RM000001RSO0C5X.html)

C
GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) (LandCruiser RM000001RSO0BZX.html)
A


3.READ VALUE USING INTELLIGENT TESTER (PARKING BRAKE SW)

  1. Turn the ignition switch off.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

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

    ABS/VSC/TRC
    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 5
OK


4.READ VALUE USING INTELLIGENT TESTER (BRAKE WARNING LIGHT)

  1. Turn the ignition switch off.

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

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

    ABS/VSC/TRC
    Tester Display
    		Measurement Item/Range
    		Normal Condition
    		Diagnostic Note
    Brake Warning Light
    		Brake warning light/ ON or OFF
    		ON: Warning light on
    OFF: Warning light off
    		-

  1. When performing the Brake Warning Light Active Test, check Brake Warning Light in the Data List (LandCruiser RM000001DWY02VX.html).

    ABS/VSC/TRC
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Brake Warning Light
    		Brake 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 (for LHD)
    		B
    Does not change between ON and OFF (for RHD)
    		C
    OFF
    		Changes between ON and OFF
    		A
    Does not change between ON and OFF (for LHD)
    		B
    Does not change between ON and OFF (for RHD)
    		C


B
REPLACE MASTER CYLINDER SOLENOID (LandCruiser RM00000171U02DX.html)

C
GO TO MASTER CYLINDER SOLENOID (LandCruiser RM00000171U02EX.html)
A

GO TO METER / GAUGE SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) (LandCruiser RM000002Z4L055X.html)

5.INSPECT PARKING BRAKE SWITCH

  1. Disconnect the G77 parking brake switch connector.



    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Brake Control Dynamic Control Systems.Anti-Lock Brake System.Vehicle Stability Control System (For Hydraulic Brake Booster) Brake Warning Light Remains On

  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 applied
    (Switch pin not pushed in)
    		Below 1 Ω
    Parking brake released
    (Switch pin pushed in)
    		10 kΩ or higher
    Text in Illustration
    *a
    		Component without harness connected
    (Parking Brake Switch)


NG
REPLACE PARKING BRAKE SWITCH ASSEMBLY (LandCruiser RM000003D75013X.html)
OK


6.CHECK HARNESS AND CONNECTOR (PARKING BRAKE SWITCH - MAIN BODY ECU)

  1. Disconnect the G77 parking brake switch connector.

  1. Remove the main body ECU (LandCruiser RM000003WBO05FX.html).

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    G77-1 - A-12 (PKB)
    		Always
    		Below 1 Ω
    G77-1 - Body ground
    		Always
    		10 kΩ or higher


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)