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Inspection Procedure

NOTE: When replacing the skid control ECU, perform the following operations:
  • Initialization of linear solenoid valve and calibration (see INITIALIZATION  )
  • Yaw rate and acceleration sensor zero point calibration (see CALIBRATION  )
  1. CHECK HARNESS AND CONNECTOR (BRAKE CONTROL POWER SUPPLY - BATTERY AND BODY GROUND) 
    1. Disconnect the S49 power supply connector.
    2. Measure the voltage according to the value(s) in the table below

      Standard voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      S49-5 (IG1) - Body ground Power switch ON (IG) 11 to 14 V
      Fig 1: Identifying S49 Connector Terminals
      G05774040Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Condition Specified Condition
      S49-14 (GND) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (SKID CONTROL ECU - BRAKE CONTROL POWER SUPPLY ASSEMBLY) 
    1. Disconnect the A19 and A21 ECU connectors
    2. Disconnect the S49 power supply connector
    3. Measure the resistance according to the value(s) in the table below

      Standard resistance 

      RESISTANCE SPECIFICATION

      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
      G05774041Courtesy 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 power 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 REFERENCE

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

    B: USE SIMULATION METHOD TO CHECK  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    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 REFERENCE

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

    B: REPLACE BRAKE CONTROL POWER SUPPLY ASSEMBLY  (See REMOVAL  )

    A: REPLACE SKID CONTROL ECU  (See REMOVAL  )

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