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Inspection Procedure

  1. CHECK WHETHER ENGINE STARTS AFTER STEERING LOCK INITIALIZATION 
    1. Open and close the driver door when the engine switch is off.
    2. Check that the engine starts.

      OK: Engine starts. 

      HINT:

      After the battery runs out, the engine may not start if the steering lock ECU has not been initialized (lock / unlock may not be recorded) through the procedure described above.

    OK: SYSTEM OK 

    NG: GO TO NEXT STEP 

  2. CHECK WHETHER DTC OUTPUT RECURS (MAIN BODY ECU AND CERTIFICATION ECU) 
    1. Clear the DTCs (see DTC CHECK / CLEAR  ).

      HINT:

      After all DTCs are cleared, check if the trouble occurs again 5 seconds after the engine switch is turned on (IG).

    2. Check for DTCs again.

      OK: No DTC is output. 

    NG: GO TO DTC CHART (See  DIAGNOSTIC TROUBLE CODE CHART   ) 

    OK: GO TO NEXT STEP 

  3. CHECK ENGINE SWITCH (SWITCH CONDITION) 
    1. Ensure the key is inside the cabin.
    2. With the brake pedal released, check that the power source mode changes as shown below each time the engine switch is pushed.

      OK: off → on (ACC) → on (IG) → off 

    NG: GO TO  POWER SOURCE MODE DOES NOT CHANGE  

    OK: GO TO NEXT STEP 

  4. CHECK BASIC FUNCTION 
    1. Ensure that there is fuel in the fuel tank and the key is inside the cabin.
    2. Depress the brake pedal with the shift lever in P or N, and keep depressing the pedal.
    3. Check that the engine cranks when the engine switch is pressed.

      OK: Engine cranks. 

    OK: Go to step   9 

    NG: GO TO NEXT STEP 

  5. READ VALUE OF INTELLIGENT TESTER OR TECHSTREAM (PARK / NEUTRAL POSITION SWITCH) 
    1. Use the Data List to check if the park / neutral position switch is functioning properly.
      1. Intelligent tester

        MAIN BODY 

        INTELLIGENT TESTER MAIN BODY REFERENCE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        N SW / C SW Park / neutral position switch/ON or OFF ON: Shift lever in P or N
        OFF: Shift lever in R or D        		 -
      2. Techstream

        Main Body 

        TECHSTREAM MAIN BODY REFERENCE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        Neutral SW / Clutch SW Park / neutral position switch/ON or OFF ON: Shift lever in P or N
        OFF: Shift lever in R or D        		 -

        OK: When the shift lever is in P or N, ON is displayed on the tester. 

    NG: REPAIR OR REPLACE PARK / NEUTRAL POSITION SWITCH  (See REMOVAL )

    OK: GO TO NEXT STEP 

  6. READ VALUE OF INTELLIGENT TESTER OR TECHSTREAM (STOP LIGHT SWITCH) 
    1. Use the Data List to check if the stop light switch is functioning properly.
      1. Intelligent tester

        MAIN BODY 

        INTELLIGENT TESTER MAIN BODY REFERENCE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        STOP LIGHT SW Stop Light switch/ON or OFF ON: Brake pedal is depressed
        OFF: Brake pedal is released        		 -
      2. Techstream

        Main Body 

        TECHSTREAM MAIN BODY REFERENCE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        Stop Light SW Stop Light switch/ON or OFF ON: Brake pedal is depressed
        OFF: Brake pedal is released        		 -

        OK: When the brake pedal is depressed, ON is displayed on the tester. 

    NG: REPAIR OR REPLACE STOP LIGHT SWITCH  (See REMOVAL )

    OK: GO TO NEXT STEP 

  7. CHECK STEERING LOCK SYSTEM 
    1. When the engine switch is on (ACC), check that the steering lock can be released.

      OK: Steering lock can be released. 

    NG: GO TO STEERING LOCK SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    OK: GO TO NEXT STEP 

  8. INSPECT MAIN BODY ECU 
    Fig 1: Identifying Terminals Of A68 Main Body ECU Connector
    G04943838Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A68 main body ECU connector.
    2. Depress the brake pedal with the shift lever in P or N, and keep depressing the pedal.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      MAIN BODY ECU

      Tester Connection Condition Specified Condition
      A68-4 (STSW) - Body ground When the engine cranks by pressing the engine switch. 11 to 14 V

    NG: GO TO SFI SYSTEM (CRANKING HOLDING FUNCTION CIRCUIT)  (See HOW TO PROCEED WITH TROUBLESHOOTING )

    OK: REPLACE MAIN BODY ECU 

  9. READ VALUE OF INTELLIGENT TESTER OR TECHSTREAM (ENGINE START REQUEST) 
    1. Use the Data List to check if the engine start request is functioning properly.
      1. Intelligent tester

        SMART ACCESS 

        INTELLIGENT TESTER SMART ACCESS REFERENCE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        START RQST Starter request signal/Yes or No YES: ID code box receives immobiliser unset signal
        NO: ID code box does not receive immobiliser unset signal        		 -
      2. Techstream

        Smart Access 

        TECHSTREAM SMART ACCESS REFERENCE

        Tester Display Measurement Item/Range Normal Condition Diagnostic Note
        Engine Start Request Starter request signal/Yes or No YES: ID code box receives immobiliser unset signal
        NO: ID code box does not receive immobiliser unset signal        		 -

        OK: When ID code box receives immobilizer unset signal, YES is displayed on tester. 

    NG: REPLACE CERTIFICATION ECU 

    OK: REPLACE ID CODE BOX 

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