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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 S49 power supply connector.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      S49-5 (IG1) - Body ground Always 11 to 14 V
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      S49-14 (GND) - Body ground Always Below 1 Ω
      Fig 1: Identifying S49 Power Supply Connector Terminals
      G04949669Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

    OK: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE CONTROL POWER SUPPLY) 
    1. Disconnect the A21 ECU connector.
    2. Disconnect the S49 power supply connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A19-8 (ENA) - S49-12 (ENA) Always Below 1 Ω
      A21-41 (FAIL) - S49-13 (FAIL) Always Below 1 Ω
      A19-8 (ENA) - Body ground Always 10 kΩ or higher
      A21-41 (FAIL) - Body ground Always 10 kΩ or higher
      Fig 2: Identifying A19, A21 And S49 Connector Terminals
      G04949670Courtesy 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

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

    B: END 

    A: Go to Next Step 

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

      Result 

      RESULT CHART

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

    B: REPLACE BRAKE CONTROL POWER SUPPLY  (See REMOVAL  )

    A: REPLACE SKID CONTROL ECU  (See REMOVAL  )

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