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Inspection Procedure

  1. READ VALUE OF HAND-HELD TESTER (VEHICLE SPEED SIGNAL) 
    1. Operate the hand-held tester according to the steps on the display and select "DATA LIST".

    ABS: 

    HAND-HELD TESTER VALUE

    Item Measurement Item/ Range (Display) Normal Condition Diagnostic Note
    (FR/FL/RR/RL) Wheel Speed Vehicle speed/Min.; 0 km/h, Max.: 255km/h(158mph) Almost same as actual speed (When driving) -

    OK: 

    1. Vehicle speed displayed on the tester is almost the same as the actual vehicle speed. 

    NG: GO TO BRAKE CONTROL SYSTEM (See  HOW TO PROCEED WITH TROUBLESHOOTING  ) 

    OK: Go to next step 

  2. INSPECT COMBINATION METER ASSY 

    INSPECTION USING OSCILLOSCOPE 

    1. Check the input signal wave form.
      1. Remove the combination meter assay with connectors still connected.
      2. Connect the oscilloscope to terminal C6-25 and body ground.
      3. Start the engine.
        Fig 1: Connecting Oscilloscope To Terminal C6-25 And Body Ground
        G03065175Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Check the signal wave form according to the condition(s) in the table shown in SIGNAL WAVE CONDITION(S) .
    SIGNAL WAVE CONDITION(S)

    Item Condition
    Tool setting 5 V/DIV, 20 ms/DIV
    Vehicle condition Driving at approx. 20 km/h (12.4 mph)

    OK: 

    1. As shown in  Fig 2 

    HINT:

    As vehicle speed increases, the cycle of the signal wave form narrows.

    Fig 2: Identifying Waveform Graph
    G03065176Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 3 

    OK: REPLACE COMBINATION METER ASSY (See  ON-VEHICLE INSPECTION  ) 

  3. CHECK HARNESS AND CONNECTOR (BETWEEN BRAKE ACTUATOR ASSY AND COMBINATION METER ASSY) (See  HOW TO PROCEED WITH TROUBLESHOOTING  ) 
    1. Disconnect the C6 and S1 connectors.
    2. Measure the resistance according to the value(s) in the table shown in BRAKE ACTUATOR ASSY AND COMBINATION METER ASSY TERMINAL RESISTANCE .

    Standard: 

    BRAKE ACTUATOR ASSY AND COMBINATION METER ASSY TERMINAL RESISTANCE

    Tester connection Condition Specified condition
    C6-25 - Body ground Always 10 kΩ or higher
    C6-25 - S1-26 Always Below 1 Ω
    Fig 3: Identifying Brake Actuator Assy And Combination Meter Assy Connector
    G03065177Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. INSPECT BRAKE ACTUATOR ASSY 
    1. Disconnect the S1 connector.
    2. Measure the voltage according to the value(s) in the table shown in BRAKE ACTUATOR ASSY TERMINAL VOLTAGE .

      Standard: 

      BRAKE ACTUATOR ASSY TERMINAL VOLTAGE

      Tester connection Condition Specified condition
      S1-26 - Body ground Ignition switch ON 10 to 14 V
    3. Measure the resistance according to the value(s) in the table shown in BRAKE ACTUATOR ASSY TERMINAL RESISTANCE .

      Standard: 

      BRAKE ACTUATOR ASSY TERMINAL RESISTANCE

      Tester connection Condition Specified condition
      S1-2 - Body ground Always Below 1 Ω
      Fig 4: Identifying Brake Actuator Assy Connector
      G03065178Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE COMBINATION METER ASSY (See  ON-VEHICLE INSPECTION  ) 

    OK: REPLACE BRAKE ACTUATOR ASSY (See  REPLACEMENT  ) 

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