DSD Information System
Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis >> Brakes >> Parking Brake System >> Electric Parking Brake System (Except HV) - Diagnostic Codes & Symptom Tests >> ELECTRIC PARKING BRAKE SYSTEM (for Gasoline Model) >> Electric Parking Brake does not Operate [12/2019 - 10/2022] >> Procedure

Electric Parking Brake does not Operate [12/2019 - 10/2022]: Procedure

  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check if CAN communication system DTCs are output.

      Chassis > Brake/EPB > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      DTCs are output B

    Result: 

    B 

    GO TO CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - 10/2022] 

    Result: 

    A 

    See step  2

  2. VEHICLE OPERATION CHECK 
    1. With the wheels not contacting the ground, check the condition of the rear wheels when the electric parking brake is operating and not operating.

      Refer to ON-VEHICLE INSPECTION [12/2019 - ]

      Result

      Result Proceed to
      Lock and release operation is normal and parking brake indicator light turns off or blinks (red) A
      Lock and release operation is malfunctioning and parking brake indicator light illuminates (red) or turns off according to switch operation B
      Lock and release operation is malfunctioning and parking brake indicator light turns off or blinks (red) C

    Result: 

    B 

    INSPECT REAR BRAKE 

    Result: 

    C 

    See step  4

    Result: 

    A 

    See step  3

  3. INSPECT COMBINATION METER ASSEMBLY 
    1. Perform the Active Test of the combination meter assembly using the GTS.

      Body Electrical > Combination Meter > Active Test 

      Tester Display
      Indicat. Park
    2. Check the combination meter assembly.

      OK

      Parking brake indicator light (red) turns on or off in accordance with GTS operation.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to  REMOVAL [12/2019 - 10/2022] 

    Result: 

    NG 

    GO TO METER / GAUGE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [12/2019 - ] 

  4. CHECK HARNESS AND CONNECTOR (+BS TERMINAL VOLTAGE) 
    1. Turn the ignition switch off.
    2. Disconnect the A39 skid control ECU (brake actuator assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY907396Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Actuator Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      A39-14 (+BS) - Body ground Always 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL VOLTAGE) 
    1. Turn the ignition switch off.
    2. Disconnect the A39 skid control ECU (brake actuator assembly) connector.
    3. Measure the voltage according to the value(s) in the table below.
      GTY907397Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Actuator Assembly))

      Standard Voltage

      Tester Connection Condition Specified Condition
      A39-45 (IG1) - Body ground Ignition switch ON 11 to 14 V*1
      10.5 to 16 V*2

      *1: w/o Stop and Start System

      *2: w/ Stop and Start System

      Result

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

    Result: 

    A 

    REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to  REMOVAL [12/2019 - 10/2022] 

    Result: 

    B 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    C 

    INSPECT STOP AND START SYSTEM (BACKUP BOOST CONVERTER CIRCUIT). Refer to  Backup Boost Converter Circuit [12/2019 - 10/2022] 

Diesel-Data.com