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Inspection Procedure

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 the steering angle sensor (see CHECK FOR INTERMITTENT PROBLEMS  ).

      Skid control ECU: 

      INTERMITTENT PROBLEMS

      Item (Display) Measurement Item / Range (Display) Normal Condition
      STEERING OPN Steering sensor open detection / ERROR or NORMAL ERROR: Momentary interruption
      NORMAL: Normal

      OK: 

      There are no momentary interruptions. 

      HINT:

      Perform the above inspection before removing the sensor and connector.

    NG:  GO TO step  4

    OK: GO TO Next Step 

  2. CHECK DTC 
    1. Clear the DTC (see DTC CHECK / CLEAR  ).
    2. Turn the power switch OFF.
    3. Turn the power switch ON (IG) again and check that no CAN communication system DTC is output.
    4. Drive the vehicle and turn the steering wheel to the right and left at a speed of 35 km/h (24 mph) and check that no speed sensor and yaw rate sensor DTCs are output.

      Result 

      RESULT

      Condition Proceed to
      No CAN communication system DTC and the speed sensor or yaw rate sensor DTC are output. A
      CAN communication system DTC is output. B
      Speed sensor or yaw rate sensor DTC is output. C

      HINT:

      • If there is a malfunction in the speed sensor or the yaw rate sensor, an abnormal value may be output although the steering angle sensor is normal.
      • If the speed sensor and the yaw rate sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.

    B: REPAIR CAN COMMUNICATION SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    C: REPAIR CIRCUIT INDICATED BY OUTPUT CODE (See  DIAGNOSTIC TROUBLE CODE CHART   ) 

    A: GO TO Next Step 

  3. CHECK WIRE HARNESS (STEERING ANGLE SENSOR - BODY GROUND) 
    1. Remove the steering wheel and the column cover lower.
    2. Disconnect the L19 sensor connector.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      L19-1 (IG) - Body ground Power switch ON (IG) 10 to 14 V
      L19-3 (BAT) - Body ground Always 10 to 14 V
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      L19-2 (ESS) - Body ground Power switch OFF Below 1 Ω
      Fig 1: Identifying L19 Connector Terminals
      G05305955Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

      If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE ", refer back to the table and proceed to the next step.

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG, BAT OR ESS CIRCUIT) 

    OK: REPLACE STEERING ANGLE SENSOR (See  REMOVAL   ) 

  4. REPAIR OR REPLACE HARNESS OR CONNECTOR (STEERING ANGLE SENSOR TO SKID CONTROL ECU) 
  5. RECONFIRM DTC 
    1. Clear the DTC (see DTC CHECK / CLEAR  ).
    2. Turn the power switch ON (READY).
    3. Drive the vehicle and turn the steering wheel to the right and left at a speed of 35 km/h (24 mph) or more.
    4. Check if the same DTC is recorded (see DTC CHECK / CLEAR  ).

      Result 

      RESULT

      Condition Proceed to
      DTC (C1231/31) is not output A
      DTC (C1231/31) is output B

      HINT:

      If troubleshooting has been carried out according to the "PROBLEM SYMPTOMS TABLE ", refer back to the table and proceed to the next step.

    B:  GO TO step  2

    A: END