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Home >> Lexus >> 2007 >> GS 450h >> Repair and Diagnosis >> Electrical >> Starter >> Starting >> Smart Access System With Push-Button Start >> Power Source Mode does not Change to ON (READY) >> Inspection Procedure
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Inspection Procedure

  1. CHECK WHETHER HYBRID SYSTEM STARTS AFTER STEERING LOCK INITIALIZATION 
    1. Open and close the driver door when the power switch is OFF.
    2. Check that the engine (hybrid) starts.

      OK: Engine (hybrid) starts. 

      HINT:

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

    OK: END (SYSTEM IS OK) 

    NG: GO TO Next Step 

  2. CHECK FOR DTC (EACH SYSTEM) 
    1. Delete the DTCs.

      HINT:

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

    2. Check for DTCs again.

      Result 

      RESULT REFERENCE

      Result Proceed to
      DTC is not output A
      DTC is output B

      HINT:

      "Each system" means the hybrid control system, engine immobiliser system, electrical steering lock, SFI system and smart access system.

    B:  GO TO DTC CHART  (EACH SYSTEM)

    A: GO TO Next Step 

  3. CHECK SWITCH CONDITION 
    1. Ensure the electrical key is inside the cabin.
    2. Check that the power source mode changes as shown below each time the power 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. READ VALUE OF INTELLIGENT TESTER (STEERING LOCK CONDITION) 
    1. Check the DATA LIST for proper functioning of the steering lock condition.

      Power source control ECU 

      POWER SOURCE CONTROL ECU - DATA LIST REFERENCE

      Item Measurement Item / Display (Range) Normal Condition
      STR UNLOCK SW Steering lock condition / ON or OFF ON: Steering is unlocked
      OFF: Steering is locked

      OK: ON (steering is unlocked) appears on screen. 

    NG: GO TO ELECTRIC STEERING LOCK 

    OK: GO TO NEXT STEP 

  5. READ VALUE OF INTELLIGENT TESTER (STOP LIGHT SWITCH) 
    1. Check the DATA LIST for proper functioning of the stop light switch.

      Power source control ECU 

      POWER SOURCE CONTROL ECU - DATA LIST REFERENCE

      Item Measurement Item / Display (Range) Normal Condition
      STOP LAMP SW1 Stop light switch signal / ON or OFF ON: Brake pedal depressed
      OFF: Brake pedal released

      OK: ON (brake pedal depressed) appears on screen. 

    NG:  GO TO step  12

    OK: GO TO Next Step 

  6. CHECK STEERING LOCK 
    1. When the power switch is ON (ACC), check that the steering lock can be released.

      OK: Steering lock can be released. 

    NG: GO TO ELECTRIC STEERING LOCK 

    OK: GO TO Next Step 

  7. CHECK POWER SOURCE CONTROL ECU 
    1. Measure the output voltage of the power source control ECU.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      39 (STSW) - Body ground Power switch pressed with brake pedal depressed → After approx. 1 sec. has passed, release power switch 10 to 14 V → Below 1 V
      Fig 1: Identifying Power Source Control ECU Connector
      G05303627Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG:  GO TO step  15

    OK: GO TO Next Step 

  8. READ VALUE OF INTELLIGENT TESTER (L CODE) 
    1. Check the DATA LIST for proper functioning of the L code check.

      Certification ECU 

      CERTIFICATION ECU - DATA LIST REFERENCE

      Item Measurement Item / Display (Range) Normal Condition
      L CODE CHK L code check / OK or NG OK: L code certification result is normal
      NG: L code certification result is abnormal

      OK: OK (L code check result is normal) appears on screen. 

    NG:  GO TO step  16

    OK: GO TO Next Step 

  9. READ VALUE OF INTELLIGENT TESTER (START REQUEST) 
    1. Check the DATA LIST for proper functioning of the engine (hybrid) start request.

      Certification ECU 

      CERTIFICATION ECU - DATA LIST REFERENCE

      Item Measurement Item / Display (Range) Normal Condition
      START RQST Engine (hybrid) start request signal / YES or NO YES: Engine (hybrid) start
      NO: Engine (hybrid) stop

      OK: Start request is OK. 

    NG:  GO TO step  17

    OK: GO TO Next Step 

  10. READ VALUE OF INTELLIGENT TESTER (S CODE) 
    1. Check the DATA LIST for proper functioning of the S code check.

      Certification ECU 

      CERTIFICATION ECU - DATA LIST REFERENCE

      Item Measurement Item / Display (Range) Normal Condition
      S CODE CHK S code check / OK or NG OK: S code certification result is normal
      NG: S code certification result is abnormal

      OK: OK (S code check result is normal) appears on screen. 

    NG:  GO TO step  17

    OK: GO TO Next Step 

  11. REPLACE ID CODE BOX 
    1. Temporarily replace the ID code box with a new or normally functioning one.
    2. Check that the engine (hybrid) starts normally.

      OK: Engine (hybrid) starts normally. 

    NG:  GO TO HYBRID CONTROL SYSTEM

    OK: END (ID CODE BOX IS FAULTY) 

  12. INSPECT FUSE (STOP SW) 
    1. Remove the STOP SW fuse from main body ECU RH.
    2. Measure the resistance of the fuse.

      Standard resistance: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: GO TO Next Step 

  13. INSPECT STOP LIGHT SWITCH 
    1. Inspect the stop light switch (see STOP LIGHT SWITCH ).

    NG: REPLACE STOP LIGHT SWITCH 

    OK: GO TO Next Step 

  14. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - BATTERY) 
    1. Disconnect the K73 ECU connector.
    2. Measure the voltage of the wire harness side connector.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      K73-1 (STP) - Body ground Brake pedal depressed 10 to 14 V
    3. Fig 2: Identifying K73 ECU Connector
      G05303656Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE POWER SOURCE CONTROL ECU 

  15. CHECK WIRE HARNESS (POWER SOURCE CONTROL ECU - HV CONTROL ECU) 
    1. Disconnect the K73 ECU connector.
    2. Disconnect the A54 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      K73-39 (STSW) - A54-22 (ST2) Below 1 Ω
      K73-39 (STSW) or A54-22 (ST2) -Body ground 10 kΩ or higher
    4. Fig 3: Identifying Power Source Control ECU And HV Control ECU Connector
      G05303626Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE POWER SOURCE CONTROL ECU 

  16. REPLACE STEERING LOCK ECU 
    1. Temporarily replace the steering lock ECU with a new or normally functioning one.
    2. Check that the engine (hybrid) starts normally.

      OK: Engine (hybrid) starts normally. 

    NG: REPLACE ID CODE BOX 

    OK: END (STEERING LOCK ECU IS FAULTY) 

  17. REPLACE CERTIFICATION ECU 
    1. Temporarily replace the certification ECU with a new or normally functioning one.
    2. Check that the engine (hybrid) starts normally.

      OK: Engine (hybrid) starts normally. 

    NG: REPLACE ID CODE BOX 

    OK: END (CERTIFICATION ECU IS FAULTY)