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Inspection Procedure

  1. READ VALUE OF INTELLIGENT TESTER (START SWITCH 1 and 2) 
    1. Check the DATA LIST for proper functioning of the start switch 1 and 2.

      Power source control ECU 

      POWER SOURCE CONTROL ECU - DATA LIST REFERENCE

      Item Measurement Item/Display (Range) Normal Condition
      START SW 1 Start Switch 1 / ON or OFF ON: Power switch pushed
      OFF: Power switch not pushed
      START SW 2 Start Switch 2 / ON or OFF ON: Power switch pushed
      OFF: Power switch not pushed

      OK: ON (power switch ON (IG)) appears on the screen. 

    OK: REPLACE POWER SOURCE CONTROL ECU 

    NG: GO TO Next Step 

  2. INSPECT POWER SWITCH 
    1. Remove the power switch.
    2. Measure the resistance of the switch.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Switch Condition Specified Condition
      7 (SS1) - 5 (GND) Pushed Below 1 Ω
      2 (SS2) - 5 (GND) Pushed Below 1 Ω
      7 (SS1) - 5 (GND) Not pushed 10 kΩ or higher
      2 (SS2) - 5 (GND) Not pushed 10 kΩ or higher
      Fig 1: Identifying Power Switch Connector Terminal
      G05303629Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE POWER SWITCH 

    OK: GO TO Next Step 

  3. CHECK WIRE HARNESS (POWER SWITCH - POWER SOURCE CONTROL ECU AND BODY GROUND) 
    1. Disconnect the K29 switch connector.
    2. Disconnect the K73 ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      STANDARD RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      K29-7 (SS1) - K73-14 (SSW1) Below 1 Ω
      K29-2 (SS2) - K73-37 (SSW2) Below 1 Ω
      K29-5 (GND) - Body ground Below 1 Ω
      K29-7 (SS1) or K73-14 (SSW1) - Body ground 10 kΩ or higher
      K29-2 (SS2) or K73-37 (SSW2) - Body ground 10 kΩ or higher
    4. Fig 2: Identifying Power Switch And Power Source Control ECU And Body Ground
      G05303630Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE POWER SOURCE CONTROL ECU