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Inspection Procedure

NOTE: When replacing the skid control ECU, perform initialization of linear solenoid valve and calibration (see INITIALIZATION  ).

HINT:

  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION) 
    1. Using the intelligent tester, check for any momentary interruption in the wire harness and connectors between the skid control ECU and steering angle sensor (see CHECK FOR INTERMITTENT PROBLEMS  ).

      Skid control ECU 

      SKID CONTROL ECU DIAGNOSTIC CHART

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      STEERING SEN Steering sensor open detection / OPN-DET or NORMAL NORMAL: Normal condition -

      OK: There are no momentary interruptions. 

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  2. READ VALUE OF INTELLIGENT TESTER (STEERING ANGLE SENSOR) 
    1. Check the DATA LIST for proper functioning of the steering angle sensor.

      Skid control ECU 

      SKID CONTROL ECU DIAGNOSTIC CHART

      Item Measurement Item / Range (Display) Normal Condition Diagnostic Note
      STEERING ANG Steering sensor/ Min.: -1152 deg, Max.: 1150.875 deg Left turn: Increase
      Right turn: Decrease
      -

      OK: Steering angle value should change. 

    OK: REPLACE SKID CONTROL ECU 

    NG: Go to Next Step 

  3. CHECK WIRE HARNESS (STEERING ANGLE SENSOR - BATTERY AND BODY GROUND) 
    1. Remove the steering wheel and the column lower cover.
    2. Disconnect the S13 sensor connector.
    3. Turn the power switch ON (READY).
    4. Measure the voltage of the wire harness side connector.

      Standard voltage 

      VOLTAGE SPECIFICATION CHART

      Tester Connection Specified Condition
      S13-1 (IG) - S13-2(ESS) 10 to 14 V
      S13-3(BAT) - S13-2(ESS) 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 1: Identifying S13 Sensor Connector And Wire Harness Side
    G05189243Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE STEERING ANGLE SENSOR