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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (see INITIALIZATION ).
  1. INSPECT BRAKE CONTROL POWER SUPPLY 
    1. Disconnect the brake control power supply connector.
    2. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      U27-5 (IG1) - Body ground 10 to 14 V
    3. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      U27-14 (GND) - Body ground Below 1 Ω
    Fig 1: Identifying Brake Control Power Supply Connector Terminals
    G05297105Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 OR GND CIRCUIT) 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU TO BRAKE CONTROL POWER SUPPLY) 
    1. Disconnect the skid control ECU and brake control power supply connector.
    2. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      A13-8 (ENA) - U27-12 (ENA) Below 1 Ω
      A13-23 (FAIL) - U27-13 (FAIL) Below 1 Ω
    3. Measure the resistance according to the value(s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

      Tester Connection Specified Condition
      A13-8 (ENA) - Body ground 10 kΩ or higher
      A13-23 (FAIL) - Body ground 10 kΩ or higher
    Fig 2: Identifying Skid Control ECU And Brake Control Power Supply Connector Terminals
    G05297106Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. RECONFIRM DTC 
    1. Clear the DTC (see DTC CHECK / CLEAR ).
    2. Turn the engine switch on (IG).
    3. Check if the same DTC is recorded (see DTC CHECK / CLEAR ).

      HINT:

      Reinstall the sensor, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.

    Result 

    RESULT CHART

    Display (DTC Output) Proceed To
    DTC (C1378/44) is not output A
    DTC (C1378/44) is output B

    B: Go to step 4 

    A: END 

  4. CHECK FREEZE FRAME DATA 
    1. Check the information code from the FREEZE FRAME DATA  memorized when the DTC (C1378/44) is stored .

    Result 

    RESULT CHART

    Condition Proceed To
    Information code is not output A
    Information code (112) is output B

    B: REPLACE BRAKE CONTROL POWER SUPPLY 

    A: REPLACE SKID CONTROL ECU 

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